Techniques for communicating on an uplink in a shared radio frequency spectrum band

ABSTRACT

Techniques are described for wireless communication. One method includes detecting a first reference signal received from a user equipment (UE) in a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) received over a shared radio frequency spectrum band; identifying a reference TTI in which the first reference signal is received; determining a contention window size usable by the UE to contend for access to the shared radio frequency spectrum band; and transmitting an indication of the determined contention window size to the UE.

CROSS REFERENCES

The present Application for Patent is a Divisional of U.S. patentapplication Ser. No. 15/605,707 by Yerramalli et al., entitled“Techniques For Communicating on an Uplink in a Shared Radio FrequencySpectrum Band,” filed May 25, 2017, which claims priority to U.S.Provisional Patent Application No. 62/365,291 by Yerramalli et al.,entitled “Techniques For Communicating on an Uplink in a Shared RadioFrequency Spectrum Band,” filed Jul. 21, 2016, each of which areassigned to the assignee hereof and expressly incorporated by referenceherein in their entirety.

BACKGROUND Field of the Disclosure

The present disclosure relates to, for example, wireless communicationsystems, and more particularly to techniques for communicating on anuplink in a shared radio frequency spectrum band.

Description of Related Art

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems.

By way of example, a wireless multiple-access communication system mayinclude a number of base stations, each simultaneously supportingcommunication for multiple communication devices, otherwise known asuser equipment (UEs). A base station may communicate with UEs ondownlink channels (e.g., for transmissions from a base station to a UE)and uplink channels (e.g., for transmissions from a UE to a basestation).

Some modes of communication may enable communication between a basestation and a UE over a shared radio frequency spectrum band, or overdifferent radio frequency spectrum bands (e.g., a dedicated radiofrequency spectrum band and a shared radio frequency spectrum band).With increasing data traffic in cellular networks that use a dedicatedradio frequency spectrum band, offloading of at least some data trafficto a shared radio frequency spectrum band may provide a mobile networkoperator (MNO) (or cellular operator) with opportunities for enhanceddata transmission capacity. Use of a shared radio frequency spectrumband may also provide service in areas where access to a dedicated radiofrequency spectrum band is unavailable.

SUMMARY

Before transmitting an uplink transmission in a shared radio frequencyspectrum band, a UE may contend for access to the shared radio frequencyspectrum band by performing a listen before talk (LBT) procedure. TheLBT procedure may be performed during a contention window having acontention window size. The contention window size may be adjusted(e.g., increased or decreased) based at least in part on a success orfailure of transmissions made to a network access device over the sharedradio frequency spectrum band. Techniques are described in the presentdisclosure for adjusting a contention window size, used by a UE, basedat least in part on determinations made by the UE or by a network accessdevice. Techniques are also described for configuring other aspects ofuplink transmissions, and other aspects of communications over a sharedradio frequency spectrum band.

In one example, a method for wireless communication at a network accessdevice is described. The method may include detecting a first referencesignal received from a UE in a reference scheduled transmission burstincluding a plurality of contiguous transmission time intervals (TTIs)received over a shared radio frequency spectrum band, identifying areference TTI in which the first reference signal is received, anddetermining a contention window size usable by the UE to contend foraccess to the shared radio frequency spectrum band. The determinedcontention window size may be based at least in part on: a triggering ofaperiodic channel state information (CSI) without a physical uplinkshared channel (PUSCH) on the reference TTI, a decoding of a physicaluplink control channel (PUCCH) with cyclic redundancy check (CRC)scheduled in the reference TTI, a decoding of a random access preamblescheduled on a physical random access channel (PRACH) in the referenceTTI, a decoding of a first scheduled uplink transmission associated witha random access procedure and received in the reference TTI, or acombination thereof. The method may also include transmitting anindication of the determined contention window size to the UE.

In one example, an apparatus for wireless communication at a networkaccess device is described. The apparatus may include means fordetecting a first reference signal received from a UE in a referencescheduled transmission burst including a plurality of contiguous TTIsreceived over a shared radio frequency spectrum band, means foridentifying a reference TTI in which the first reference signal isreceived, and means for determining a contention window size usable bythe UE to contend for access to the shared radio frequency spectrumband. The determined contention window size may be based at least inpart on: a triggering of aperiodic CSI without a PUSCH on the referenceTTI, a decoding of a PUCCH with CRC scheduled in the reference TTI, adecoding of a random access preamble scheduled on a PRACH in thereference TTI, a decoding of a first scheduled uplink transmissionassociated with a random access procedure and received in the referenceTTI, or a combination thereof. The apparatus may also include means fortransmitting an indication of the determined contention window size tothe UE.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include aprocessor, and memory in electronic communication with the processor.The processor and the memory may be configured to detect a firstreference signal received from a UE in a reference scheduledtransmission burst including a plurality of contiguous TTIs receivedover a shared radio frequency spectrum band, to identify a reference TTIin which the first reference signal is received, and to determine acontention window size usable by the UE to contend for access to theshared radio frequency spectrum band. The determined contention windowsize may be based at least in part on: a triggering of aperiodic CSIwithout a PUSCH on the reference TTI, a decoding of a PUCCH with CRCscheduled in the reference TTI, a decoding of a random access preamblescheduled on a PRACH in the reference TTI, a decoding of a firstscheduled uplink transmission associated with a random access procedureand received in the reference TTI, or a combination thereof. Theprocessor and the memory may also be configured to transmit anindication of the determined contention window size to the UE.

In one example, a non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a network accessdevice is described. The code may be executable by a processor to detecta first reference signal received from a UE in a reference scheduledtransmission burst including a plurality of contiguous TTIs receivedover a shared radio frequency spectrum band, to identify a reference TTIin which the first reference signal is received, and to determine acontention window size usable by the UE to contend for access to theshared radio frequency spectrum band. The determined contention windowsize may be based at least in part on: a triggering of aperiodic CSIwithout a PUSCH on the reference TTI, a decoding of a PUCCH with CRCscheduled in the reference TTI, a decoding of a random access preamblescheduled on a PRACH in the reference TTI, a decoding of a firstscheduled uplink transmission associated with a random access procedureand received in the reference TTI, or a combination thereof. The codemay also be executable by the processor to transmit an indication of thedetermined contention window size to the UE.

In one example, a method for wireless communication at a UE isdescribed. The method may include receiving at least one uplink grantfor a reference scheduled transmission burst including a plurality ofcontiguous TTIs transmitted over a shared radio frequency spectrum band.At least a first uplink grant in the plurality of uplink grants mayinclude: a first indication that the first uplink grant is associatedwith a first scheduled TTI of the reference scheduled transmissionburst, a second indication of a position of the first scheduled TTIwithin the reference scheduled transmission burst, or a combinationthereof. The method may also include transmitting during at least oneTTI of the reference scheduled transmission burst, in accordance withthe at least one uplink grant. The transmitting may begin during a firsttransmission TTI. The method may also include receiving an indication ofa reference TTI, the reference TTI being used for transmission duringthe reference scheduled transmission burst, and determining a contentionwindow size usable by the UE to contend for access to the shared radiofrequency spectrum band. The contention window size may be determinedbased at least in part on a relationship between the first scheduledTTI, the reference TTI, and the first transmission TTI. In some cases,the relationship may include the first transmission TTI being earlierthan the reference TTI, the first transmission TTI being later than thereference TTI, or the first transmission TTI being the same as thereference TTI.

In some examples of the method, each uplink grant for the referencescheduled transmission burst may include an indication of the positionof the first scheduled TTI of the reference scheduled transmissionburst. In some examples, the indication of the reference TTI may berelative to the first scheduled TTI.

In one example, an apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving at least oneuplink grant for a reference scheduled transmission burst including aplurality of contiguous TTIs transmitted over a shared radio frequencyspectrum band. At least a first uplink grant in the plurality of uplinkgrants may include: a first indication that the first uplink grant isassociated with a first scheduled TTI of the reference scheduledtransmission burst, a second indication of a position of the firstscheduled TTI within the reference scheduled transmission burst, or acombination thereof. The apparatus may also include means fortransmitting during at least one TTI of the reference scheduledtransmission burst, in accordance with the at least one uplink grant.The transmitting may begin during a first transmission TTI. Theapparatus may also include means for receiving an indication of areference TTI, the reference TTI being used for transmission during thereference scheduled transmission burst, and means for determining acontention window size usable by the UE to contend for access to theshared radio frequency spectrum band. The contention window size may bedetermined based at least in part on a relationship between the firstscheduled TTI, the reference TTI, and the first transmission TTI. Insome cases, the relationship may include the first transmission TTIbeing earlier than the reference TTI, the first transmission TTI beinglater than the reference TTI, or the first transmission TTI being thesame as the reference TTI.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive at least one uplink grant for areference scheduled transmission burst including a plurality ofcontiguous TTIs transmitted over a shared radio frequency spectrum band.At least a first uplink grant in the plurality of uplink grants mayinclude: a first indication that the first uplink grant is associatedwith a first scheduled TTI of the reference scheduled transmissionburst, a second indication of a position of the first scheduled TTIwithin the reference scheduled transmission burst, or a combinationthereof. The processor and the memory may also be configured to transmitduring at least one TTI of the reference scheduled transmission burst,in accordance with the at least one uplink grant. The transmitting maybegin during a first transmission TTI. The processor and the memory mayalso be configured to receive an indication of a reference TTI, thereference TTI being used for transmission during the reference scheduledtransmission burst, and to determine a contention window size usable bythe UE to contend for access to the shared radio frequency spectrumband. The contention window size may be determined based at least inpart on a relationship between the first scheduled TTI, the referenceTTI, and the first transmission TTI. In some cases, the relationship mayinclude the first transmission TTI being earlier than the reference TTI,the first transmission TTI being later than the reference TTI, or thefirst transmission TTI being the same as the reference TTI.

In one example, a non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive at leastone uplink grant for a reference scheduled transmission burst includinga plurality of contiguous TTIs transmitted over a shared radio frequencyspectrum band. At least a first uplink grant in the plurality of uplinkgrants may include: a first indication that the first uplink grant isassociated with a first scheduled TTI of the reference scheduledtransmission burst, a second indication of a position of the firstscheduled TTI within the reference scheduled transmission burst, or acombination thereof. The code may also be executable by the processor totransmit during at least one TTI of the reference scheduled transmissionburst, in accordance with the at least one uplink grant. Thetransmitting may begin during a first transmission TTI. The code mayalso be executable by the processor to receive an indication of areference TTI, the reference TTI being used for transmission during thereference scheduled transmission burst, and to determine a contentionwindow size usable by the UE to contend for access to the shared radiofrequency spectrum band. The contention window size may be determinedbased at least in part on a relationship between the first scheduledTTI, the reference TTI, and the first transmission TTI. In some cases,the relationship may include the first transmission TTI being earlierthan the reference TTI, the first transmission TTI being later than thereference TTI, or the first transmission TTI being the same as thereference TTI.

In one example, another method for wireless communication at a UE isdescribed. The method may include transmitting a reference scheduledtransmission burst including a plurality of contiguous TTIs over ashared radio frequency spectrum band, and identifying a hybrid automaticrepeat request (HARQ) process corresponding to a reference TTI. Thereference TTI may be a first TTI of the plurality of contiguous TTIs forwhich a HARQ acknowledgement is received. The method may also includeidentifying an instance of the HARQ process associated with a TTIsubsequent to the reference TTI. The instance of the HARQ process may beidentified based at least in part on: whether the TTI is within thereference scheduled transmission burst or a subsequent transmissionburst, whether the TTI includes aperiodic CSI without a PUSCH, or acombination thereof. The method may also include determining acontention window size used to contend for access to the shared radiofrequency spectrum band, in which the determining based at least in parton a state of a new data indicator (NDI) associated with the identifiedinstance of the HARQ process.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for transmitting a referencescheduled transmission burst including a plurality of contiguous TTIsover a shared radio frequency spectrum band, and means for identifying aHARQ process corresponding to a reference TTI. The reference TTI may bea first TTI of the plurality of contiguous TTIs for which a HARQacknowledgement is received. The apparatus may also include means foridentifying an instance of the HARQ process associated with a TTIsubsequent to the reference TTI. The instance of the HARQ process may beidentified based at least in part on: whether the TTI is within thereference scheduled transmission burst or a subsequent transmissionburst, whether the TTI includes aperiodic CSI without a PUSCH, or acombination thereof. The apparatus may also include means fordetermining a contention window size used to contend for access to theshared radio frequency spectrum band, in which the determining is basedat least in part on a state of a NDI associated with the identifiedinstance of the HARQ process.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to transmit a reference scheduled transmissionburst including a plurality of contiguous TTIs over a shared radiofrequency spectrum band, and to identify a HARQ process corresponding toa reference TTI. The reference TTI may be a first TTI of the pluralityof contiguous TTIs for which a HARQ acknowledgement is received. Theprocessor and the memory may also be configured to identify an instanceof the HARQ process associated with a TTI subsequent to the referenceTTI. The instance of the HARQ process may be identified based at leastin part on: whether the TTI is within the reference scheduledtransmission burst or a subsequent transmission burst, whether the TTIincludes aperiodic CSI without a PUSCH, or a combination thereof. Theprocessor and the memory may also be configured to determine acontention window size used to contend for access to the shared radiofrequency spectrum band, in which the determining is based at least inpart on a state of a NDI associated with the identified instance of theHARQ process.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to transmit areference scheduled transmission burst including a plurality ofcontiguous TTIs over a shared radio frequency spectrum band, and toidentify a HARQ process corresponding to a reference TTI. The referenceTTI may be a first TTI of the plurality of contiguous TTIs for which aHARQ acknowledgement is received. The code may also be executable by theprocessor to identify an instance of the HARQ process associated with aTTI subsequent to the reference TTI. The instance of the HARQ processmay be identified based at least in part on: whether the TTI is withinthe reference scheduled transmission burst or a subsequent transmissionburst, whether the TTI includes aperiodic CSI without a PUSCH, or acombination thereof. The code may also be executable by the processor todetermine a contention window size used to contend for access to theshared radio frequency spectrum band, the determining based at least inpart on a state of a NDI associated with the identified instance of theHARQ process.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving, in a common physicaldownlink control channel (CPDCCH), a first indication of a remainingchannel occupancy time (RCOT) for which a network access device hasaccess to a shared radio frequency spectrum band, and a secondindication of a pause time during which the network access device willnot transmit over the shared radio frequency spectrum band. The methodmay also include determining, based at least in part on the RCOT,whether a size of an uplink transmission of the UE allows the UE totransmit the uplink transmission within a maximum channel occupancy time(MCOT) for which the network access device has access to the sharedradio frequency spectrum band, and entering a power saving mode duringat least a part of the pause time.

In some examples of the method, the RCOT may include the pause time. Insome examples, the RCOT may not include the pause time.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving, in a CPDCCH, afirst indication of a RCOT for which a network access device has accessto a shared radio frequency spectrum band, and a second indication of apause time during which the network access device will not transmit overthe shared radio frequency spectrum band. The apparatus may also includemeans for determining, based at least in part on the RCOT, whether asize of an uplink transmission of the UE allows the UE to transmit theuplink transmission within a MCOT for which the network access devicehas access to the shared radio frequency spectrum band, and means forentering a power saving mode during at least a part of the pause time.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive, in a CPDCCH, a first indication ofa RCOT for which a network access device has access to a shared radiofrequency spectrum band, and a second indication of a pause time duringwhich the network access device will not transmit over the shared radiofrequency spectrum band. The processor and the memory may also beconfigured to determine, based at least in part on the RCOT, whether asize of an uplink transmission of the UE allows the UE to transmit theuplink transmission within a MCOT for which the network access devicehas access to the shared radio frequency spectrum band, and to enter apower saving mode during at least a part of the pause time.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive, in aCPDCCH, a first indication of a RCOT for which a network access devicehas access to a shared radio frequency spectrum band, and a secondindication of a pause time during which the network access device willnot transmit over the shared radio frequency spectrum band. The code mayalso be executable by the processor to determine, based at least in parton the RCOT, whether a size of an uplink transmission of the UE allowsthe UE to transmit the uplink transmission within a MCOT for which thenetwork access device has access to the shared radio frequency spectrumband, and to enter a power saving mode during at least a part of thepause time.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving, in a downlink TTI of ascheduled transmission burst received over a shared radio frequencyspectrum band, an indication of a downlink-uplink TTI configurationbeginning with the downlink TTI; and determining, based at least in parton the downlink-uplink TTI configuration beginning with the downlinkTTI, a timing of a next downlink TTI in the scheduled transmissionburst. In some cases, the downlink-uplink configuration may include anumber of upcoming downlink TTIs, a number of uplink TTIs, or acombination thereof.

In some examples, the method may include receiving, in each of at leastone additional downlink TTI of the scheduled transmission burst, anadditional indication of an additional downlink-uplink TTI configurationfollowing the additional downlink TTI. In some examples, the method mayinclude receiving, in the downlink TTI, at least one of: a secondindication of a downlink TTI duration, a third indication of an uplinkTTI duration, or a combination thereof. In some examples, the downlinkTTI may include a downlink subframe and the downlink-uplink TTIconfiguration may include a downlink-uplink subframe configuration.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving, in a downlinkTTI of a scheduled transmission burst received over a shared radiofrequency spectrum band, an indication of a downlink-uplink TTIconfiguration beginning with the downlink TTI; and means fordetermining, based at least in part on the downlink-uplink TTIconfiguration beginning with the downlink TTI, a timing of a nextdownlink TTI in the scheduled transmission burst. In some cases, thedownlink-uplink configuration may include a number of upcoming downlinkTTIs, a number of uplink TTIs, or a combination thereof.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive, in a downlink TTI of a scheduledtransmission burst received over a shared radio frequency spectrum band,an indication of a downlink-uplink TTI configuration beginning with thedownlink TTI; and to determine, based at least in part on thedownlink-uplink TTI configuration beginning with the downlink TTI, atiming of a next downlink TTI in the scheduled transmission burst. Insome cases, the downlink-uplink configuration may include a number ofupcoming downlink TTIs, a number of uplink TTIs, or a combinationthereof.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to wirelesscommunication at a UE, the code executable by a processor to receive, ina downlink TTI of a scheduled transmission burst received over a sharedradio frequency spectrum band, an indication of a downlink-uplink TTIconfiguration beginning with the downlink TTI; and to determine, basedat least in part on the downlink-uplink TTI configuration beginning withthe downlink TTI, a timing of a next downlink TTI in the scheduledtransmission burst. In some cases, the downlink-uplink configuration mayinclude a number of upcoming downlink TTIs, a number of uplink TTIs, ora combination thereof.

In one example, another method for wireless communication at a UE isdescribed. The method may include transmitting a buffer status report(BSR); receiving from a network access device, in response totransmitting the BSR, an indicator of a LBT priority class boundary;selecting a LBT priority class based at least in part on a type of datato be transmitted over a shared radio frequency spectrum band and theLBT priority class boundary; and contending for access to the sharedradio frequency spectrum band based at least in part on the selected LBTpriority class.

In some examples of the method, the LBT priority class boundary mayinclude at least one of: a highest LBT priority class usable by the UE,a lowest LBT priority class usable by the UE, or a combination thereof.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for transmitting a BSR; meansfor receiving from a network access device, in response to transmittingthe BSR, an indicator of a LBT priority class boundary; means forselecting a LBT priority class based at least in part on a type of datato be transmitted over a shared radio frequency spectrum band and thelowest LBT priority class boundary; and means for contending for accessto the shared radio frequency spectrum band based at least in part onthe selected LBT priority class.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to transmit a BSR; receive from a networkaccess device, in response to transmitting the BSR, an indicator of aLBT priority class boundary; to select a LBT priority class based atleast in part on a type of data to be transmitted over a shared radiofrequency spectrum band and the lowest LBT priority class boundary; andto contend for access to the shared radio frequency spectrum band basedat least in part on the selected LBT priority class.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to transmit a BSR;to receive from a network access device, in response to transmitting theBSR, an indicator of a LBT priority class boundary; to select a LBTpriority class based at least in part on a type of data to betransmitted over a shared radio frequency spectrum band and the lowestLBT priority class boundary; and to contend for access to the sharedradio frequency spectrum band based at least in part on the selected LBTpriority class.

In one example, another method for wireless communication at a UE isdescribed. The method may include transmitting a first type of BSRincluding an indication of an amount of data to be transmitted for eachof a plurality of LBT priority classes; and receiving from a networkaccess device, in response to transmitting the first BSR, an indicationof a LBT priority class to be used by the UE when contending for accessto a shared radio frequency spectrum band.

In some examples, the method may include selecting the first type of BSRfrom a plurality of BSR types including at least the first type of BSRand a second type of BSR. In some examples, the second type of BSR mayinclude a Long Term Evolution (LTE)/LTE-Advanced (LTE-A) type of BSR. Insome examples, the first type of BSR may be selected based at least inpart on a BSR selection criterion. In some examples, the BSR selectioncriterion may include receiving data to transmit, in which the data isassociated with a LBT priority class satisfying a threshold LBT priorityclass.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for transmitting a first typeof BSR including an indication of an amount of data to be transmittedfor each of a plurality of LBT priority classes; and means for receivingfrom a network access device, in response to transmitting the first typeof BSR, an indication of a LBT priority class to be used by the UE whencontending for access to a shared radio frequency spectrum band.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to transmit a first type of B SR including anindication of an amount of data to be transmitted for each of aplurality of LBT priority classes; and to receive from a network accessdevice, in response to transmitting the first type of BSR, an indicationof a LBT priority class to be used by the UE when contending for accessto a shared radio frequency spectrum band.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to transmit a firsttype of BSR including an indication of an amount of data to betransmitted for each of a plurality of LBT priority classes; and toreceive from a network access device, in response to transmitting thefirst type of BSR, an indication of a LBT priority class to be used bythe UE when contending for access to a shared radio frequency spectrumband.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving a first uplink grant fortransmitting over a shared radio frequency spectrum band, in which thefirst uplink grant associated with a first LBT priority class;performing a first LBT procedure based at least in part on the first LBTpriority class to contend for access to the shared radio frequencyspectrum band, in which the first LBT procedure concludes at a LBTstate; determining, based at least in part on the LBT state, to nottransmit over the shared radio frequency spectrum band in accordancewith the first uplink grant; receiving a second uplink grant fortransmitting over the shared radio frequency spectrum band, in which thesecond uplink grant associated with a second LBT priority class; andperforming a second LBT procedure based at least in part on the secondLBT priority class, the first LBT priority class, and the LBT state tocontend for access to the shared radio frequency spectrum band.

In some examples, the method may include determining the first LBTpriority class and the second LBT priority class are a same LBT priorityclass, and initializing the second LBT procedure based at least in parton the LBT state. In some examples, the method may include determiningthe first LBT priority class and the second LBT priority class aredifferent LBT priority classes, adjusting the LBT state based at leastin part on a difference between the first LBT priority class and thesecond LBT priority class, and initializing the second LBT procedurebased at least in part on the adjusted LBT state.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving a first uplinkgrant for transmitting over a shared radio frequency spectrum band, inwhich the first uplink grant associated with a first LBT priority class;means for performing a first LBT procedure based at least in part on thefirst LBT priority class to contend for access to the shared radiofrequency spectrum band, in which the first LBT procedure concludes at aLBT state; means for determining, based at least in part on the LBTstate, to not transmit over the shared radio frequency spectrum band inaccordance with the first uplink grant; means for receiving a seconduplink grant for transmitting over the shared radio frequency spectrumband, in which the second uplink grant associated with a second LBTpriority class; and means for performing a second LBT procedure based atleast in part on the second LBT priority class, the first LBT priorityclass, and the LBT state to contend for access to the shared radiofrequency spectrum band.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive a first uplink grant fortransmitting over a shared radio frequency spectrum band, in which thefirst uplink grant associated with a first LBT priority class; toperform a first LBT procedure based at least in part on the first LBTpriority class to contend for access to the shared radio frequencyspectrum band, in which the first LBT procedure concluding at a LBTstate; to determine, based at least in part on the LBT state, to nottransmit over the shared radio frequency spectrum band in accordancewith the first uplink grant; to receive a second uplink grant fortransmitting over the shared radio frequency spectrum band, in which thesecond uplink grant associated with a second LBT priority class; and toperform a second LBT procedure based at least in part on the second LBTpriority class, the first LBT priority class, and the LBT state tocontend for access to the shared radio frequency spectrum band.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive a firstuplink grant for transmitting over a shared radio frequency spectrumband, in which the first uplink grant associated with a first LBTpriority class; to perform a first LBT procedure based at least in parton the first LBT priority class to contend for access to the sharedradio frequency spectrum band, in which the first LBT procedureconcluding at a LBT state; to determine, based at least in part on theLBT state, to not transmit over the shared radio frequency spectrum bandin accordance with the first uplink grant; to receive a second uplinkgrant for transmitting over the shared radio frequency spectrum band, inwhich the second uplink grant associated with a second LBT priorityclass; and to perform a second LBT procedure based at least in part onthe second LBT priority class, in which the first LBT priority class,and the LBT state to contend for access to the shared radio frequencyspectrum band.

In one example, another method for wireless communication at a networkaccess device is described. The method may include identifying feedbackreceived from a UE for a downlink reference TTI of a transmissionopportunity (TxOP) over a shared radio frequency spectrum band, in whichthe TxOP may include at least one downlink TTI and at least one uplinkTTI; identifying an uplink TTI, of the TxOP, for which schedulinginformation is transmitted in the downlink reference TTI; anddetermining a contention window size usable by the network access deviceto contend for access to the shared radio frequency spectrum band, for anext TxOP, based at least in part on the identified feedback and ascheduled uplink transmission in the identified uplink TTI.

In some examples, determining the contention window size based at leastin part on the scheduled uplink transmission in the identified uplinkTTI may include determining the contention window size based at least inpart on a decoding of at least one channel including: a scheduled PUSCH,or a scheduled PUCCH, or a scheduled PRACH, or a combination thereof. Insome examples, determining the contention window size based at least inpart on the decoding of the at least one channel may include determiningthe contention window size based least in part onacknowledgement/non-acknowledgement (ACK/NACK) feedback for the at leastone channel. In some examples, the at least one downlink TTI may includeat least one downlink subframe, and the at least one uplink TTI mayinclude at least one uplink subframe.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include means foridentifying feedback received from a UE for a downlink reference TTI ofa TxOP over a shared radio frequency spectrum band, in which the TxOPmay include at least one downlink TTI and at least one uplink TTI; meansfor identifying an uplink TTI, of the TxOP, for which schedulinginformation is transmitted in the downlink reference TTI; and means fordetermining a contention window size usable by the network access deviceto contend for access to the shared radio frequency spectrum band, for anext TxOP, based at least in part on the identified feedback and ascheduled uplink transmission in the identified uplink TTI.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include aprocessor, and memory in electronic communication with the processor.The processor and the memory may be configured to identify feedbackreceived from a UE for a downlink reference TTI of a TxOP over a sharedradio frequency spectrum band, in which the TxOP may include at leastone downlink TTI and at least one uplink TTI; to identify an uplink TTI,of the TxOP, for which scheduling information is transmitted in thedownlink reference TTI; and to determine a contention window size usableby the network access device to contend for access to the shared radiofrequency spectrum band, for a next TxOP, based at least in part on theidentified feedback and a scheduled uplink transmission in theidentified uplink TTI.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a network accessdevice is described. The code may be executable by a processor toidentify feedback received from a UE for a downlink reference TTI of aTxOP over a shared radio frequency spectrum band, in which the TxOP mayinclude at least one downlink TTI and at least one uplink TTI; toidentify an uplink TTI, of the TxOP, for which scheduling information istransmitted in the downlink reference TTI; and to determine a contentionwindow size usable by the network access device to contend for access tothe shared radio frequency spectrum band, for a next TxOP, based atleast in part on the identified feedback and a scheduled uplinktransmission in the identified uplink TTI.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving scheduling information foran uplink transmission to be made over a plurality of carriers of ashared radio frequency spectrum band, identifying a carrier of theplurality of carriers for which to perform a first type of LBTprocedure, performing the first type of LBT procedure for the identifiedcarrier, performing a second type of LBT procedure for each carrier ofthe plurality of carriers other than the identified carrier, andtransmitting the uplink transmission over the plurality of carriersbased at least in part on the performance of the first type of LBTprocedure for the identified carrier and the performance of the secondtype of LBT procedure for each carrier other than the identifiedcarrier. The second type of LBT procedure may have a shorter contentionwindow than the first type of LBT procedure.

In some examples of the method, identifying the carrier may include oneof: identifying the carrier from an indication received from a networkaccess device, or independently identifying the carrier.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving schedulinginformation for an uplink transmission to be made over a plurality ofcarriers of a shared radio frequency spectrum band, means foridentifying a carrier of the plurality of carriers for which to performa first type of LBT procedure, means for performing the first type ofLBT procedure for the identified carrier, means for performing a secondtype of LBT procedure for each carrier of the plurality of carriersother than the identified carrier, and means for transmitting the uplinktransmission over the plurality of carriers based at least in part onthe performance of the first type of LBT procedure for the identifiedcarrier and the performance of the second type of LBT procedure for eachcarrier other than the identified carrier. The second type of LBTprocedure may have a shorter contention window than the first type ofLBT procedure.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive scheduling information for an uplinktransmission to be made over a plurality of carriers of a shared radiofrequency spectrum band, to identify a carrier of the plurality ofcarriers for which to perform a first type of LBT procedure, to performthe first type of LBT procedure for the identified carrier, to perform asecond type of LBT procedure for each carrier of the plurality ofcarriers other than the identified carrier, and to transmit the uplinktransmission over the plurality of carriers based at least in part onthe performance of the first type of LBT procedure for the identifiedcarrier and the performance of the second type of LBT procedure for eachcarrier other than the identified carrier. The second type of LBTprocedure may have a shorter contention window than the first type ofLBT procedure.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receivescheduling information for an uplink transmission to be made over aplurality of carriers of a shared radio frequency spectrum band, toidentify a carrier of the plurality of carriers for which to perform afirst type of LBT procedure, to perform the first type of LBT procedurefor the identified carrier, to perform a second type of LBT procedurefor each carrier of the plurality of carriers other than the identifiedcarrier, and to transmit the uplink transmission over the plurality ofcarriers based at least in part on the performance of the first type ofLBT procedure for the identified carrier and the performance of thesecond type of LBT procedure for each carrier other than the identifiedcarrier. The second type of LBT procedure may have a shorter contentionwindow than the first type of LBT procedure.

In one example, another method for wireless communication at a networkaccess device is described. The method may include scheduling an uplinktransmission to be made by a UE over a plurality of carriers of a sharedradio frequency spectrum band; and transmitting, to the UE, anindication of a single carrier of the plurality of carriers for which toperform a first type of LBT procedure.

In some examples, transmitting the indication of the single carrier mayinclude: transmitting the indication of the single carrier in uplinkdownlink control information (DCI) for the single carrier, ortransmitting the indication of the single carrier in uplink DCI for eachcarrier of the plurality of carriers.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include means forscheduling an uplink transmission to be made by a UE over a plurality ofcarriers of a shared radio frequency spectrum band; and means fortransmitting, to the UE, an indication of a single carrier of theplurality of carriers for which to perform a first type of LBTprocedure.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include aprocessor, and memory in electronic communication with the processor.The processor and the memory may be configured to schedule an uplinktransmission to be made by a UE over a plurality of carriers of a sharedradio frequency spectrum band; and to transmit, to the UE, an indicationof a single carrier of the plurality of carriers for which to perform afirst type of LBT procedure.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a network accessdevice is described. The code may be executable by a processor toschedule an uplink transmission to be made by a UE over a plurality ofcarriers of a shared radio frequency spectrum band; and to transmit, tothe UE, an indication of a single carrier of the plurality of carriersfor which to perform a first type of LBT procedure.

In one example, another method for wireless communication at a UE isdescribed. The method may include identifying a type of LBT procedure tobe performed for contending for access to a shared radio frequencyspectrum band. The identified type of LBT procedure may include a firsttype of LBT procedure or a second type of LBT procedure. The method mayalso include identifying an energy detection threshold associated withthe identified type of LBT procedure. The identified energy detectionthreshold may include a first energy detection threshold for the firsttype of LBT procedure or a second energy detection threshold for thesecond type of LBT procedure. The first energy detection threshold maybe lower than the second energy detection threshold. The method may alsoinclude performing the identified type of LBT procedure based at leastin part on the identified energy detection threshold to contend foraccess to the shared radio frequency spectrum band.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for identifying a type of LBTprocedure to be performed for contending for access to a shared radiofrequency spectrum band. The identified type of LBT procedure mayinclude a first type of LBT procedure or a second type of LBT procedure.The apparatus may also include means for identifying an energy detectionthreshold associated with the identified type of LBT procedure. Theidentified energy detection threshold may include a first energydetection threshold for the first type of LBT procedure or a secondenergy detection threshold for the second type of LBT procedure. Thefirst energy detection threshold may be lower than the second energydetection threshold. The apparatus may also include means for performingthe identified type of LBT procedure based at least in part on theidentified energy detection threshold to contend for access to theshared radio frequency spectrum band.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to identify a type of LBT procedure to beperformed for contending for access to a shared radio frequency spectrumband. The identified type of LBT procedure may include a first type ofLBT procedure or a second type of LBT procedure. The processor and thememory may be configured to identify an energy detection thresholdassociated with the identified type of LBT procedure. The identifiedenergy detection threshold may include a first energy detectionthreshold for the first type of LBT procedure or a second energydetection threshold for the second type of LBT procedure. The firstenergy detection threshold may be lower than the second energy detectionthreshold. The processor and the memory may be configured to perform theidentified type of LBT procedure based at least in part on theidentified energy detection threshold to contend for access to theshared radio frequency spectrum band.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to identify a typeof LBT procedure to be performed for contending for access to a sharedradio frequency spectrum band. The identified type of LBT procedure mayinclude a first type of LBT procedure or a second type of LBT procedure.The code may also be executable by the processor to identify an energydetection threshold associated with the identified type of LBTprocedure. The identified energy detection threshold may include a firstenergy detection threshold for the first type of LBT procedure or asecond energy detection threshold for the second type of LBT procedure.The first energy detection threshold may be lower than the second energydetection threshold. The code may also be executable by the processor toperform the identified type of LBT procedure based at least in part onthe identified energy detection threshold to contend for access to theshared radio frequency spectrum band.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving an indication that the UEcannot update a countdown counter associated with performance of a LBTprocedure during a TTI in which the UE receives a transmission,determining the UE is receiving a transmission during a TTI, andrefraining from at least one of: performing a LBT procedure during theTTI, updating the countdown counter associated with performance of theLBT procedure during the TTI, or a combination thereof.

In some examples of the method, the indication that the UE cannot updatethe countdown counter may be received in at least one of: radio resourcecontrol (RRC) signaling, a system information block (SIB), or DCI.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving an indicationthat the UE cannot update a countdown counter associated withperformance of a LBT procedure during a TTI in which the UE receives atransmission, means for determining the UE is receiving a transmissionduring a TTI, and means for refraining from at least one of: performinga LBT procedure during the TTI, updating the countdown counterassociated with performance of the LBT procedure during the TTI, or acombination thereof.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive an indication that the UE cannotupdate a countdown counter associated with performance of a LBTprocedure during a TTI in which the UE receives a transmission, todetermine the UE is receiving a transmission during a TTI, and torefrain from at least one of: performing a LBT procedure during the TTI,updating the countdown counter associated with performance of the LBTprocedure during the TTI, or a combination thereof.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive anindication that the UE cannot update a countdown counter associated withperformance of a LBT procedure during a TTI in which the UE receives atransmission, to determine the UE is receiving a transmission during aTTI, and to refrain from at least one of: performing a LBT procedureduring the TTI, updating the countdown counter associated withperformance of the LBT procedure during the TTI, or a combinationthereof.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving an indication of atransmission parameter for an uplink transmission to be made over ashared radio frequency spectrum band during at least one TTI,identifying a content of the uplink transmission in each TTI of the atleast one TTI, and scaling the transmission parameter for at least afirst TTI based at least in part on an identified content of the uplinktransmission in the first TTI.

In some examples of the method, the identified content may include atleast one of: a number of resource elements (REs), a number of puncturedsymbol periods, a first presence of a PUCCH, a second presence of aPRACH, a third presence of a sounding reference signal (SRS), or acombination thereof. In some examples, the transmission parameter mayinclude at least one of: a transport block size (TBS), a modulation andcoding scheme (MCS), or a combination thereof. In some examples, scalingthe transmission parameter may include one of: switching to a fixedalternative transmission parameter, or computing an alternativetransmission parameter based at least in part on a comparison of theidentified content to a nominal content.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving an indicationof a transmission parameter for an uplink transmission to be made over ashared radio frequency spectrum band during at least one TTI, means foridentifying a content of the uplink transmission in each TTI of the atleast one TTI, and means for scaling the transmission parameter for atleast a first TTI based at least in part on an identified content of theuplink transmission in the first TTI.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive an indication of a transmissionparameter for an uplink transmission to be made over a shared radiofrequency spectrum band during at least one TTI, to identify a contentof the uplink transmission in each TTI of the at least one TTI, and toscale the transmission parameter for at least a first TTI based at leastin part on an identified content of the uplink transmission in the firstTTI.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive anindication of a transmission parameter for an uplink transmission to bemade over a shared radio frequency spectrum band during at least oneTTI, to identify a content of the uplink transmission in each TTI of theat least one TTI, and to scale the transmission parameter for at least afirst TTI based on an identified content of the uplink transmission inthe first TTI.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving RRC signaling from anetwork. The RRC signaling may configure HARQ ACK feedback reporting fora first carrier in a shared radio frequency spectrum band in one of: afirst mode in which the UE transmits HARQ ACK feedback is transmitted ona PUCCH on a second carrier in a dedicated radio frequency spectrumband, or a second mode in which the UE selects to transmit HARQ ACKfeedback on the PUCCH on the second carrier or on a PUSCH on the firstcarrier. The method may also include transmitting HARQ ACK feedback inaccordance with the first mode or the second mode, as configured by theRRC signaling.

In some examples of the method, the RRC signaling may configure the HARQACK feedback reporting for the first carrier in the second mode, and themethod may further include contending for access to the first carrier inthe shared radio frequency spectrum band, and selecting to transmit HARQACK feedback on the PUSCH on the first carrier based at least in part onwinning contention for access to the first carrier.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving RRC signalingfrom a network. The RRC signaling may configure HARQ ACK feedbackreporting for a first carrier in a shared radio frequency spectrum bandin one of: a first mode in which the UE transmits HARQ ACK feedback istransmitted on a PUCCH on a second carrier in a dedicated radiofrequency spectrum band, or a second mode in which the UE selects totransmit HARQ ACK feedback on the PUCCH on the second carrier or on aPUSCH on the first carrier. The apparatus may also include means fortransmitting HARQ ACK feedback in accordance with the first mode or thesecond mode, as configured by the RRC signaling.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive RRC signaling from a network. TheRRC signaling may configure HARQ ACK feedback reporting for a firstcarrier in a shared radio frequency spectrum band in one of: a firstmode in which the UE transmits HARQ ACK feedback is transmitted on aPUCCH on a second carrier in a dedicated radio frequency spectrum band,or a second mode in which the UE selects to transmit HARQ ACK feedbackon the PUCCH on the second carrier or on a PUSCH on the first carrier.The processor and the memory may also be configured to transmit HARQ ACKfeedback in accordance with the first mode or the second mode, asconfigured by the RRC signaling.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive RRCsignaling from a network. The RRC signaling may configure HARQ ACKfeedback reporting for a first carrier in a shared radio frequencyspectrum band in one of: a first mode in which the UE transmits HARQ ACKfeedback is transmitted on a PUCCH on a second carrier in a dedicatedradio frequency spectrum band, or a second mode in which the UE selectsto transmit HARQ ACK feedback on the PUCCH on the second carrier or on aPUSCH on the first carrier. The code may also be executable by aprocessor to transmit HARQ ACK feedback in accordance with the firstmode or the second mode, as configured by the RRC signaling.

In one example, another method for wireless communication at a networkaccess device is described. The method may include configuring HARQ ACKfeedback reporting for a first carrier in a shared radio frequencyspectrum in one of: a first mode in which a UE transmits HARQ ACKfeedback on a PUCCH on a second carrier in a dedicated radio frequencyspectrum band, or a second mode in which the UE selects to transmit HARQACK feedback on the PUCCH on the second carrier or on a PUSCH on thefirst carrier; transmitting an indication of the configured HARQ ACKfeedback reporting mode to the UE in RRC signaling; and receiving HARQACK feedback for the first carrier from the UE, in accordance with theconfigured HARQ ACK feedback reporting mode.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include means forconfiguring HARQ ACK feedback reporting for a first carrier in a sharedradio frequency spectrum in one of: a first mode in which a UE transmitsHARQ ACK feedback on a PUCCH on a second carrier in a dedicated radiofrequency spectrum band, or a second mode in which the UE selects totransmit HARQ ACK feedback on the PUCCH on the second carrier or on aPUSCH on the first carrier; means for transmitting an indication of theconfigured HARQ ACK feedback reporting mode to the UE in RRC signaling;and means for receiving HARQ ACK feedback for the first carrier from theUE, in accordance with the configured HARQ ACK feedback reporting mode.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include aprocessor, and memory in electronic communication with the processor.The processor and the memory may be configured to configure HARQ ACKfeedback reporting for a first carrier in a shared radio frequencyspectrum in one of: a first mode in which a UE transmits HARQ ACKfeedback on a PUCCH on a second carrier in a dedicated radio frequencyspectrum band, or a second mode in which the UE selects to transmit HARQACK feedback on the PUCCH on the second carrier or on a PUSCH on thefirst carrier; to transmit an indication of the configured HARQ ACKfeedback reporting mode to the UE in RRC signaling; and to receive HARQACK feedback for the first carrier from the UE, in accordance with theconfigured HARQ ACK feedback reporting mode.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a network accessdevice is described. The code may be executable by a processor toconfigure HARQ ACK feedback reporting for a first carrier in a sharedradio frequency spectrum in one of: a first mode in which a UE transmitsHARQ ACK feedback on a PUCCH on a second carrier in a dedicated radiofrequency spectrum band, or a second mode in which the UE selects totransmit HARQ ACK feedback on the PUCCH on the second carrier or on aPUSCH on the first carrier; to transmit an indication of the configuredHARQ ACK feedback reporting mode to the UE in RRC signaling; and toreceive HARQ ACK feedback for the first carrier from the UE, inaccordance with the configured HARQ ACK feedback reporting mode.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving an indication of an invalidPUSCH resource allocation for a TTI over a shared radio frequencyspectrum band, and transmitting aperiodic CSI without a PUSCH in theTTI.

In some examples of the method, the invalid PUSCH resource allocationmay include an invalid frequency interlace combination with a designatedbit pattern for a redundancy version (RV) and a NDI. In some examples,the method may include interpreting a HARQ identifier (ID) for the TTIas invalid.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving an indicationof an invalid PUSCH resource allocation for a TTI over a shared radiofrequency spectrum band, and means for transmitting aperiodic CSIwithout a PUSCH in the TTI.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive an indication of an invalid PUSCHresource allocation for a TTI over a shared radio frequency spectrumband, and to transmit aperiodic CSI without a PUSCH in the TTI.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive anindication of an invalid PUSCH resource allocation for a TTI over ashared radio frequency spectrum band, and to transmit aperiodic CSIwithout a PUSCH in the TTI.

In one example, another method for wireless communication at a networkaccess device is described. The method may include transmitting anindication of an invalid PUSCH resource allocation for a TTI over ashared radio frequency spectrum band, and receiving aperiodic CSIwithout a PUSCH in the TTI.

In some examples of the method, the invalid PUSCH resource allocationmay include an invalid frequency interlace combination with a designatedbit pattern for a RV and a NDI.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include means fortransmitting an indication of an invalid PUSCH resource allocation for aTTI over a shared radio frequency spectrum band, and means for receivingaperiodic CSI without a PUSCH in the TTI.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include aprocessor, and memory in electronic communication with the processor.The processor and the memory may be configured to transmit an indicationof an invalid PUSCH resource allocation for a TTI over a shared radiofrequency spectrum band, and receive aperiodic CSI without a PUSCH inthe TTI.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a network accessdevice is described. The code may be executable by a processor totransmit an indication of an invalid PUSCH resource allocation for a TTIover a shared radio frequency spectrum band, and receive aperiodic CSIwithout a PUSCH in the TTI.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving a code point associated withtransmission of aperiodic CSI over a shared radio frequency spectrumband in a TTI scheduled without a PUSCH, receiving a multi-TTI grantthat references the code point for a TTI scheduled by the multi-TTIgrant, and transmitting aperiodic CSI without a PUSCH in the TTI, inaccordance with the code point.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving a code pointassociated with transmission of aperiodic CSI over a shared radiofrequency spectrum band in a TTI scheduled without a PUSCH, means forreceiving a multi-TTI grant that references the code point for a TTIscheduled by the multi-TTI grant, and means for transmitting aperiodicCSI without a PUSCH in the TTI, in accordance with the code point.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive a code point associated withtransmission of aperiodic CSI over a shared radio frequency spectrumband in a TTI scheduled without a PUSCH, to receive a multi-TTI grantthat references the code point for a TTI scheduled by the multi-TTIgrant, and to transmit aperiodic CSI without a PUSCH in the TTI, inaccordance with the code point.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive a codepoint associated with transmission of aperiodic CSI over a shared radiofrequency spectrum band in a TTI scheduled without a PUSCH, to receive amulti-TTI grant that references the code point for a TTI scheduled bythe multi-TTI grant, and to transmit aperiodic CSI without a PUSCH inthe TTI, in accordance with the code point.

In one example, another method for wireless communication at a networkaccess device is described. The method may include identifying anexpected frequency of SRS requests; identifying an aperiodic SRS to betransmitted without a PUSCH, during a TTI, over a shared radio frequencyspectrum band; determining a contention window size to be used by a UEwhen performing a LBT procedure to contend for access to the sharedradio frequency spectrum band to transmit the aperiodic SRS, in whichthe determined contention window size based at least in part on theexpected frequency of SRS requests; and transmitting an indication ofthe determined contention window size to the UE.

In some examples of the method, the indication of the determinedcontention window size may be transmitted in RRC signaling.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include means foridentifying an expected frequency of SRS requests; means for identifyingan aperiodic SRS to be transmitted without a PUSCH, during a TTI, over ashared radio frequency spectrum band; means for determining a contentionwindow size to be used by a UE when performing a LBT procedure tocontend for access to the shared radio frequency spectrum band totransmit the aperiodic SRS, in which the determined contention windowsize based at least in part on the expected frequency of SRS requests;and means for transmitting an indication of the determined contentionwindow size to the UE.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include aprocessor, and memory in electronic communication with the processor.The processor and the memory may be configured to identify an expectedfrequency of SRS requests; to identify an aperiodic SRS to betransmitted without a PUSCH, during a TTI, over a shared radio frequencyspectrum band; to determine a contention window size to be used by a UEwhen performing a LBT procedure to contend for access to the sharedradio frequency spectrum band to transmit the aperiodic SRS, in whichthe determined contention window size based at least in part on theexpected frequency of SRS requests; and to transmit an indication of thedetermined contention window size to the UE.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a network accessdevice is described. The code may be executable by a processor toidentify an expected frequency of SRS requests; to identify an aperiodicSRS to be transmitted without a PUSCH, during a TTI, over a shared radiofrequency spectrum band; to determine a contention window size to beused by a UE when performing a LBT procedure to contend for access tothe shared radio frequency spectrum band to transmit the aperiodic SRS,in which the determined contention window size based at least in part onthe expected frequency of SRS requests; and to transmit an indication ofthe determined contention window size to the UE.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving, in downlink DCI, a triggerto transmit a SRS during a TTI; receiving scheduling information for aPUSCH to be transmitted during the TTI, in which the schedulinginformation does not include a gap for transmitting the SRS; andtransmitting, during the TTI, one of: the PUSCH rate matched around theSRS, the PUSCH punctured by the SRS, the PUSCH without the SRS, or theSRS without the PUSCH.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving, in downlinkDCI, a trigger to transmit a SRS during a TTI; means for receivingscheduling information for a PUSCH to be transmitted during the TTI, inwhich the scheduling information does not include a gap for transmittingthe SRS; and means for transmitting, during the TTI, one of: the PUSCHrate matched around the SRS, the PUSCH punctured by the SRS, the PUSCHwithout the SRS, or the SRS without the PUSCH.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive, in downlink DCI, a trigger totransmit a SRS during a TTI; to receive scheduling information for aPUSCH to be transmitted during the TTI, in which the schedulinginformation does not include a gap for transmitting the SRS; and totransmit, during the TTI, one of: the PUSCH rate matched around the SRS,the PUSCH punctured by the SRS, the PUSCH without the SRS, or the SRSwithout the PUSCH.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive, indownlink DCI, a trigger to transmit a SRS during a TTI; to receivescheduling information for a PUSCH to be transmitted during the TTI, inwhich the scheduling information does not include a gap for transmittingthe SRS; and to transmit, during the TTI, one of: the PUSCH rate matchedaround the SRS, the PUSCH punctured by the SRS, the PUSCH without theSRS, or the SRS without the PUSCH.

In one example, another method for wireless communication at a UE isdescribed. The method may include receiving a first indication of adefault initial timing advance for a first carrier in a shared radiofrequency spectrum band, in which the default initial timing advanceincludes: a timing advance of a second carrier in a dedicated radiofrequency spectrum band, and in which the first carrier and the secondcarrier are in a same timing advance group (TAG), or a static initialtiming advance, or a combination thereof. The method may also includereceiving a second indication of a default initial uplink transmitpower, and transmitting on the first carrier based at least in part onthe default initial timing advance and the default initial uplinktransmit power.

In some examples of the method, the static initial timing advance may bezero. In some examples, the default initial uplink transmit power may bea maximum uplink transmit power. In some examples, the second indicationmay be received in at least one of: a system information block, a RRCconfiguration, or a combination thereof. In some examples, the methodmay include receiving a plurality of code points indicating differentuplink transmit power adjustment steps, and a code point providing thesecond indication.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include means for receiving a firstindication of a default initial timing advance for a first carrier in ashared radio frequency spectrum band, in which the default initialtiming advance including: a timing advance of a second carrier in adedicated radio frequency spectrum band, and in which the first carrierand the second carrier are in a same TAG, or a static initial timingadvance, or a combination thereof. The apparatus may also include meansfor receiving a second indication of a default initial uplink transmitpower, and means for transmitting on the first carrier based at least inpart on the default initial timing advance and the default initialuplink transmit power.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, and memory inelectronic communication with the processor. The processor and thememory may be configured to receive a first indication of a defaultinitial timing advance for a first carrier in a shared radio frequencyspectrum band, in which the default initial timing advance including: atiming advance of a second carrier in a dedicated radio frequencyspectrum band, and in which the first carrier and the second carrier arein a same TAG, or a static initial timing advance, or a combinationthereof. The processor and the memory may also be configured to receivea second indication of a default initial uplink transmit power, and totransmit on the first carrier based at least in part on the defaultinitial timing advance and the default initial uplink transmit power.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to receive a firstindication of a default initial timing advance for a first carrier in ashared radio frequency spectrum band, in which the default initialtiming advance including: a timing advance of a second carrier in adedicated radio frequency spectrum band, and in which the first carrierand the second carrier are in a same TAG, or a static initial timingadvance, or a combination thereof. The code may also be executable bythe processor to receive a second indication of a default initial uplinktransmit power, and to transmit on the first carrier based at least inpart on the default initial timing advance and the default initialuplink transmit power.

In one example, another method for wireless communication at a networkaccess device is described. The method may include selecting, from aplurality of code points, at least one of: a first code point forcontrolling transmit power in a single TTI uplink transmission, a secondcode point for controlling transmit power in a multi-TTI uplinktransmission, a third code point associated with transmitting at amaximum transmit power during a single TTI uplink transmission or amulti-TTI uplink transmission, or a combination thereof. The first codepoint and the second code point may be associated with differenttransmit powers. The method may also include transmitting a transmitpower control (TPC) command to a UE. The TPC command may include the atleast one selected code point.

In some examples, the method may include scheduling an uplinktransmission by the UE, in which the scheduled uplink transmission mayinclude a single TTI uplink transmission or a multi-TTI uplinktransmission, and transmitting to the UE an uplink grant referencing acode point transmitted in the TPC command. In some examples, the secondcode point may identify larger uplink transmit power adjustment stepsthan the first code point.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include means forselecting from a plurality of code points, at least one of: a first codepoint for controlling transmit power in a single TTI uplinktransmission, a second code point for controlling transmit power in amulti-TTI uplink transmission, a third code point associated withtransmitting at a maximum transmit power during a single TTI uplinktransmission or a multi-TTI uplink transmission, or a combinationthereof. The first code point and the second code point may beassociated with different transmit powers. The apparatus may alsoinclude means for transmitting a TPC command to a UE. The TPC commandmay include the at least one selected code point.

In one example, another apparatus for wireless communication at anetwork access device is described. The apparatus may include aprocessor, and memory in electronic communication with the processor.The processor and the memory may be configured to select from aplurality of code points, at least one of: a first code point forcontrolling transmit power in a single TTI uplink transmission, a secondcode point for controlling transmit power in a multi-TTI uplinktransmission, a third code point associated with transmitting at amaximum transmit power during a single TTI uplink transmission or amulti-TTI uplink transmission, or a combination thereof. The first codepoint and the second code point may be associated with differenttransmit powers. The processor and the memory may also be configured totransmit a TPC command to a UE. The TPC command may include the at leastone selected code point.

In one example, another non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a network accessdevice is described. The code may be executable by a processor to selectfrom a plurality of code points, at least one of: a first code point forcontrolling transmit power in a single TTI uplink transmission, a secondcode point for controlling transmit power in a multi-TTI uplinktransmission, a third code point associated with transmitting at amaximum transmit power during a single TTI uplink transmission or amulti-TTI uplink transmission, or a combination thereof. The first codepoint and the second code point may be associated with transmit powers.The code may be executable by the processor to transmit a TPC command toa UE. The TPC command may include the at least one selected code point.

The foregoing has outlined rather broadly the techniques and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionaltechniques and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purpose ofillustration and description, and not as a definition of the limits ofthe claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the following drawings. In theappended figures, similar components or functions may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 illustrates an example of a wireless communication system, inaccordance with various aspects of the present disclosure;

FIG. 2 shows a wireless communication system in which LTE/LTE-A may bedeployed under different scenarios using a shared radio frequencyspectrum band, in accordance with various aspects of the presentdisclosure;

FIG. 3 shows a timeline of wireless communications between a basestation and number of UEs, in accordance with various aspects of thepresent disclosure;

FIG. 4 shows a timeline of wireless communications between a basestation and number of UEs, in accordance with various aspects of thepresent disclosure;

FIG. 5 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 6 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 7 shows a block diagram of a UE for use in wireless communication,in accordance with various aspects of the present disclosure;

FIG. 8 shows a block diagram of a base station for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 9 is a flow chart illustrating an example of a method for wirelesscommunication at a network access device, in accordance with variousaspects of the present disclosure;

FIG. 10 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 11 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 12 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 13 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 14 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 15 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 16 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 17 is a flow chart illustrating an example of a method for wirelesscommunication at a network access device, in accordance with variousaspects of the present disclosure;

FIG. 18 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 19 is a flow chart illustrating an example of a method for wirelesscommunication at a network access device, in accordance with variousaspects of the present disclosure;

FIG. 20 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 21 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 22 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 23 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 24 is a flow chart illustrating an example of a method for wirelesscommunication at a network access device, in accordance with variousaspects of the present disclosure;

FIG. 25 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 26 is a flow chart illustrating an example of a method for wirelesscommunication at a network access device, in accordance with variousaspects of the present disclosure;

FIG. 27 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 28 is a flow chart illustrating an example of a method for wirelesscommunication at a network access device, in accordance with variousaspects of the present disclosure;

FIG. 29 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure;

FIG. 30 is a flow chart illustrating an example of a method for wirelesscommunication at a UE, in accordance with various aspects of the presentdisclosure; and

FIG. 31 is a flow chart illustrating an example of a method for wirelesscommunication at a network access device, in accordance with variousaspects of the present disclosure.

DETAILED DESCRIPTION

Techniques are described in which a shared radio frequency spectrum bandis used for at least a portion of communications in a wirelesscommunication system. In some examples, the shared radio frequencyspectrum band may be used for Long Term Evolution (LTE) or LTE-Advanced(LTE-A) communications. The shared radio frequency spectrum band may beused in combination with, or independent from, a dedicated radiofrequency spectrum band. The dedicated radio frequency spectrum band mayinclude a radio frequency spectrum band licensed to particular users forparticular uses. The shared radio frequency spectrum band may include aradio frequency spectrum band available for Wi-Fi use, a radio frequencyspectrum band available for use by different radio access technologies,or a radio frequency spectrum band available for use by multiple mobilenetwork operators (MNOs) in an equally shared or prioritized manner.

With increasing data traffic in cellular networks that use a dedicatedradio frequency spectrum band, offloading of at least some data trafficto a shared radio frequency spectrum band may provide a cellularoperator (e.g., an operator of a public land mobile network (PLMN) or acoordinated set of base stations defining a cellular network, such as anLTE/LTE-A network) with opportunities for enhanced data transmissioncapacity. Use of a shared radio frequency spectrum band may also provideservice in areas where access to a dedicated radio frequency spectrumband is unavailable. Before communicating over a shared radio frequencyspectrum band, a transmitting apparatus may perform a listen before talk(LBT) procedure to contend for access to the shared radio frequencyspectrum band. Such a LBT procedure may include performing a clearchannel assessment (CCA) procedure (or extended CCA procedure) todetermine whether a channel of the shared radio frequency spectrum bandis available. When it is determined that the channel of the shared radiofrequency spectrum band is available, a channel reservation signal(e.g., a channel usage beacon signal (CUBS)) may be transmitted toreserve the channel. When it is determined that a channel is notavailable, a CCA procedure (or extended CCA procedure) may be performedfor the channel again at a later time.

The following description provides examples, and is not limiting of thescope, applicability, or examples set forth in the claims. Changes maybe made in the function and arrangement of elements discussed withoutdeparting from the scope of the disclosure. Various examples may omit,substitute, or add various procedures or components as appropriate. Forinstance, the methods described may be performed in an order differentfrom that described, and various steps may be added, omitted, orcombined. Also, features described with respect to some examples may becombined in other examples.

FIG. 1 illustrates an example of a wireless communication system 100, inaccordance with various aspects of the present disclosure. The wirelesscommunication system 100 may include base stations 105 (i.e., a type ofnetwork access device), UEs 115, and a core network 130. The corenetwork 130 may provide user authentication, access authorization,tracking, Internet Protocol (IP) connectivity, and other access,routing, or mobility functions. The base stations 105 may interface withthe core network 130 through backhaul links 132 (e.g., S1, etc.) and mayperform radio configuration and scheduling for communication with theUEs 115, or may operate under the control of a base station controller(not shown). In various examples, the base stations 105 may communicate,either directly or indirectly (e.g., through core network 130), witheach other over backhaul links 134 (e.g., X1, etc.), which may be wiredor wireless communication links.

The base stations 105 may wirelessly communicate with the UEs 115 viaone or more base station antennas. Each of the base station 105 sitesmay provide communication coverage for a respective geographic coveragearea 110. In some examples, a base station 105 may be referred to as anetwork access device, a base transceiver station, a radio base station,an access point, a radio transceiver, a NodeB, an eNodeB (eNB), a HomeNodeB, a Home eNodeB, or some other suitable terminology. The geographiccoverage area 110 for a base station 105 may be divided into sectorsmaking up a portion of the coverage area (not shown). The wirelesscommunication system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). There may beoverlapping geographic coverage areas 110 for different technologiesand/or different types of network access devices.

In some examples, the wireless communication system 100 may include anLTE/LTE-A network. In LTE/LTE-A networks, the term evolved Node B (eNB)may be used to describe the base stations 105. The wirelesscommunication system 100 may be a Heterogeneous LTE/LTE-A network inwhich different types of eNBs provide coverage for various geographicalregions. For example, each eNB or base station 105 may providecommunication coverage for a macro cell, a small cell, or other types ofcell. The term “cell” is a 3GPP term that can be used to describe a basestation, a carrier or component carrier associated with a base station,or a coverage area (e.g., sector, etc.) of a carrier or base station,depending on context.

A macro cell may cover a relatively large geographic area (e.g., severalkilometers in radius) and may allow unrestricted access by UEs withservice subscriptions with the network provider. A small cell may be alower-powered base station, as compared with a macro cell that mayoperate in the same or different (e.g., licensed, unlicensed, etc.)radio frequency spectrum bands as macro cells. Small cells may includepico cells, femto cells, and micro cells according to various examples.A pico cell may cover a relatively smaller geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell also may cover a relatively small geographic area(e.g., a home) and may provide restricted access by UEs having anassociation with the femto cell (e.g., UEs in a closed subscriber group(CSG), UEs for users in the home, and the like). An eNB for a macro cellmay be referred to as a macro eNB. An eNB for a small cell may bereferred to as a small cell eNB, a pico eNB, a femto eNB or a home eNB.An eNB may support one or multiple (e.g., two, three, four, and thelike) cells (e.g., component carriers).

The wireless communication system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations 105may have similar frame timing, and transmissions from different basestations 105 may be approximately aligned in time. For asynchronousoperation, the base stations 105 may have different frame timing, andtransmissions from different base stations 105 may not be aligned intime. The techniques described herein may be used for either synchronousor asynchronous operations.

The communication networks that may accommodate some of the variousdisclosed examples may be packet-based networks that operate accordingto a layered protocol stack. In the user plane, communications at thebearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based.A Radio Link Control (RLC) layer may perform packet segmentation andreassembly to communicate over logical channels. A Medium Access Control(MAC) layer may perform priority handling and multiplexing of logicalchannels into transport channels. The MAC layer may also use Hybrid ARQ(HARD) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and the base stations 105 or corenetwork 130 supporting radio bearers for the user plane data. At thephysical (PHY) layer, the transport channels may be mapped to physicalchannels.

The UEs 115 may be dispersed throughout the wireless communicationsystem 100, and each UE 115 may be stationary or mobile. A UE 115 mayalso include or be referred to by those skilled in the art as a mobilestation, a subscriber station, a mobile unit, a subscriber unit, awireless unit, a remote unit, a mobile device, a wireless device, awireless communication device, a remote device, a mobile subscriberstation, an access terminal, a mobile terminal, a wireless terminal, aremote terminal, a handset, a user agent, a mobile client, a client, orsome other suitable terminology. A UE 115 may be a cellular phone, apersonal digital assistant (PDA), a wireless modem, a wirelesscommunication device, a handheld device, a tablet computer, a laptopcomputer, a cordless phone, a wireless local loop (WLL) station, or thelike. A UE may be able to communicate with various types of basestations or other types of network access devices or network equipment,including macro eNBs, small cell eNBs, relay base stations, and thelike.

The communication links 125 shown in wireless communication system 100may include downlinks (DLs), from a base station 105 to a UE 115, oruplinks (ULs), from a UE 115 to a base station 105. The downlinks mayalso be called forward links, while the uplinks may also be calledreverse links.

In some examples, each communication link 125 may include one or morecarriers, where each carrier may be a signal made up of multiplesub-carriers (e.g., waveform signals of different frequencies) modulatedaccording to the various radio technologies described above. Eachmodulated signal may be transmitted on a different sub-carrier and maycarry control information (e.g., reference signals, control channels,etc.), overhead information, user data, etc. The communication links 125may transmit bidirectional communications using a frequency domainduplexing (FDD) operation (e.g., using paired spectrum resources) or atime domain duplexing (TDD) operation (e.g., using unpaired spectrumresources). Frame structures for FDD operation (e.g., frame structuretype 1) and TDD operation (e.g., frame structure type 2) may be defined.

In some examples of the wireless communication system 100, base stations105, or UEs 115 may include multiple antennas for employing antennadiversity schemes to improve communication quality and reliabilitybetween base stations 105 and UEs 115. Additionally or alternatively,base stations 105 or UEs 115 may employ multiple-input, multiple-output(MIMO) techniques that may take advantage of multi-path environments totransmit multiple spatial layers carrying the same or different codeddata.

The wireless communication system 100 may support operation on multiplecells or carriers, a feature which may be referred to as carrieraggregation (CA) or dual-connectivity operation. A carrier may also bereferred to as a component carrier (CC), a layer, a channel, etc. Theterms “carrier,” “component carrier,” “cell,” and “channel” may be usedinterchangeably herein. Carrier aggregation may be used with both FDDand TDD component carriers.

In an LTE/LTE-A network, a UE 115 may be configured to communicate usingup to five CCs when operating in a carrier aggregation mode ordual-connectivity mode. One or more of the CCs may be configured as a DLCC, and one or more of the CCs may be configured as a UL CC. Also, oneof the CCs allocated to a UE 115 may be configured as a primary CC(PCC), and the remaining CCs allocated to the UE 115 may be configuredas secondary CCs (SCCs).

In some examples, the wireless communication system 100 may supportoperation over a dedicated radio frequency spectrum band (e.g., a radiofrequency spectrum band licensed to particular users for particularuses) or a shared radio frequency spectrum band (e.g., a radio frequencyspectrum band that is available for Wi-Fi use, a radio frequencyspectrum band that is available for use by different radio accesstechnologies, or a radio frequency spectrum band that is available foruse by multiple MNOs in an equally shared or prioritized manner).

FIG. 2 shows a wireless communication system 200 in which LTE/LTE-A maybe deployed under different scenarios using a shared radio frequencyspectrum band, in accordance with various aspects of the presentdisclosure. More specifically, FIG. 2 illustrates examples of asupplemental downlink mode (also referred to as a licensed assistedaccess (LAA) mode), a carrier aggregation mode (also referred to as anenhanced LAA (eLAA) mode), and a standalone mode, in which LTE/LTE-A isdeployed using a shared radio frequency spectrum band. The wirelesscommunication system 200 may be an example of portions of the wirelesscommunication system 100 as described with reference to FIG. 1.Moreover, a first base station 205 and a second base station 205-a maybe examples of aspects of one or more of the base stations 105 describedwith reference to FIG. 1, while a first UE 215, a second UE 215-a, and athird UE 215-b may be examples of aspects of one or more of the UEs 115as described with reference to FIG. 1.

In the example of the supplemental downlink mode (e.g., the LAA mode) inthe wireless communication system 200, the first base station 205 maytransmit orthogonal frequency-division multiple access (OFDMA) waveformsto the first UE 215 using a downlink channel 220. The downlink channel220 may be associated with a frequency F1 in a shared radio frequencyspectrum band. The first base station 205 may transmit OFDMA waveformsto the first UE 215 using a first bidirectional link 225 and may receivesingle-carrier frequency-division multiple access (FDMA) (SC-FDMA)waveforms from the first UE 215 using the first bidirectional link 225.The first bidirectional link 225 may be associated with a frequency F4in a dedicated radio frequency spectrum band. The downlink channel 220in the shared radio frequency spectrum band and the first bidirectionallink 225 in the dedicated radio frequency spectrum band may operatecontemporaneously. The downlink channel 220 may provide a downlinkcapacity offload for the first base station 205. In some examples, thedownlink channel 220 may be used for unicast services (e.g., addressedto one UE) or for multicast services (e.g., addressed to several UEs).This scenario may occur with any service provider (e.g., a MNO) thatuses a dedicated radio frequency spectrum band and needs to relieve someof the traffic or signaling congestion.

In the example of the carrier aggregation mode (e.g., the eLAA mode) inthe wireless communication system 200, the first base station 205 maytransmit OFDMA waveforms to the second UE 215-a using a secondbidirectional link 230 and may receive OFDMA waveforms, SC-FDMAwaveforms, or resource block interleaved FDMA waveforms from the secondUE 215-a using the second bidirectional link 230. The secondbidirectional link 230 may be associated with the frequency F1 in theshared radio frequency spectrum band. The first base station 205 mayalso transmit OFDMA waveforms to the second UE 215-a using a thirdbidirectional link 235 and may receive SC-FDMA waveforms from the secondUE 215-a using the third bidirectional link 235. The third bidirectionallink 235 may be associated with a frequency F2 in a dedicated radiofrequency spectrum band. The third bidirectional link 235 may provide adownlink and uplink capacity offload for the first base station 205.Like the supplemental downlink mode (e.g., the LAA mode) describedabove, this scenario may occur with any service provider (e.g., MNO)that uses a dedicated radio frequency spectrum band and needs to relievesome of the traffic or signaling congestion.

As described above, one type of service provider that may benefit fromthe capacity offload offered by using LTE/LTE-A in a shared radiofrequency spectrum band is a traditional MNO having access rights to anLTE/LTE-A licensed radio frequency spectrum band. For these serviceproviders, an operational example may include a bootstrapped mode (e.g.,supplemental downlink, carrier aggregation) that uses the LTE/LTE-A PCCon the dedicated radio frequency spectrum band and at least one SCC onthe shared radio frequency spectrum band.

In the carrier aggregation mode, data and control may, for example, becommunicated in the dedicated radio frequency spectrum band (e.g., viathe third bidirectional link 235) while data may, for example, becommunicated in the shared radio frequency spectrum band (e.g., viasecond bidirectional link 230). The carrier aggregation mechanismssupported when using a shared radio frequency spectrum band may fallunder a hybrid frequency division duplexing-time division duplexing(FDD-TDD) carrier aggregation or a TDD-TDD carrier aggregation withdifferent symmetry across component carriers.

In one example of a standalone mode in the wireless communication system200, the second base station 205-a may transmit OFDMA waveforms to thethird UE 215-b using a bidirectional link 245 and may receive OFDMAwaveforms, SC-FDMA waveforms, or resource block interleaved FDMAwaveforms from the third UE 215-b using the bidirectional link 245. Thebidirectional link 245 may be associated with the frequency F3 in theshared radio frequency spectrum band. The standalone mode may be used innon-traditional wireless access scenarios, such as in-stadium access(e.g., unicast, multicast). An example of a type of service provider forthis mode of operation may be a stadium owner, cable company, eventhost, hotel, enterprise, or large corporation that does not have accessto a dedicated radio frequency spectrum band.

In some examples, a transmitting apparatus such as one of the basestations 105, 205, or 205-a as described with reference to FIG. 1 or 2,or one of the UEs 115, 215, 215-a, or 215-b as described with referenceto FIG. 1 or 2, may use a gating interval to gain access to a wirelesschannel of a shared radio frequency spectrum band (e.g., to a physicalchannel of the shared radio frequency spectrum band). In some examples,the gating interval may be synchronous and periodic. For example, theperiodic gating interval may be synchronized with at least one boundaryof an LTE/LTE-A radio interval. In other examples, the gating intervalmay be asynchronous. The gating interval may define the application of asharing protocol, such as an LBT protocol based on the LBT protocolspecified in European Telecommunications Standards Institute (ETSI) (EN301 893). When using a gating interval that defines the application ofan LBT protocol, the gating interval may indicate when a transmittingapparatus needs to perform a contention procedure (e.g., an LBTprocedure) such as a CCA procedure or an extended CCA (ECCA) procedure.The outcome of the CCA procedure or ECCA procedure may indicate to thetransmitting apparatus whether a wireless channel of a shared radiofrequency spectrum band is available or in use for the gating interval(e.g., an LBT radio frame or transmission burst). When a CCA procedureor ECCA procedure indicates the wireless channel is available for acorresponding LBT radio frame or transmission burst (e.g., “clear” foruse), the transmitting apparatus may reserve or use the wireless channelof the shared radio frequency spectrum band during part or all of theLBT radio frame. When a CCA procedure or ECCA procedure indicates thewireless channel is not available (e.g., that the wireless channel is inuse or reserved by another transmitting apparatus), the transmittingapparatus may be prevented from using the wireless channel during theLBT radio frame. In some examples, a transmitting apparatus may need toperform a CCA procedure or ECCA procedure for some but not otherwireless channels in a shared radio frequency spectrum band.

FIG. 3 shows a timeline 300 of wireless communications between a basestation and number of UEs, in accordance with various aspects of thepresent disclosure. The wireless communications may occur in a sharedradio frequency spectrum band. The shared radio frequency spectrum bandmay include a radio frequency spectrum band available for Wi-Fi use, aradio frequency spectrum band available for use by different radioaccess technologies, or a radio frequency spectrum band available foruse by multiple MNOs in an equally shared or prioritized manner. In someexamples, the base station(s) and UE(s) that communicate in the sharedradio frequency spectrum band may be examples of aspects of the basestations 105, 205, or 205-a and UEs 115, 215, 215-a, or 215-b asdescribed with reference to FIG. 1 or 2.

In some examples, a base station may perform a LBT procedure 305 (e.g.,a CCA procedure or ECCA procedure) at a time t0, prior to a transmissionopportunity 310. The LBT procedure 305 may be performed to contend foraccess to the shared radio frequency spectrum band during thetransmission opportunity 310. The transmission opportunity 310 may beassociated with a maximum channel occupancy time (MCOT) 315. When thebase station wins contention for access to the shared radio frequencyspectrum band for the transmission opportunity 310, the base station maytransmit to one or more UEs during a number of TTIs transmission timeintervals (TTIs) (e.g., during a number of downlink (DL) subframes). Thebase station may also schedule uplink transmissions from one or more UEsduring a number of TTIs (e.g., during a number of uplink (UL)subframes). When the base station loses contention for access to theshared radio frequency spectrum band for the transmission opportunity310, the base station may not transmit or schedule uplink transmissionsduring the transmission opportunity 310, and may have to delaycommunication with one or more UEs until a subsequent transmissionopportunity (e.g., a subsequent transmission opportunity for which thebase station wins contention for access to the shared radio frequencyspectrum band). FIG. 3 assumes the base station wins contention foraccess to the shared radio frequency spectrum band during the LBTprocedure 305.

By way of example, the timeline 300 shows a downlink period 320 followedby an uplink period 325 that ends within the transmission opportunity310. A downlink transmission may be transmitted during the downlinkperiod 320, and an uplink transmission may be transmitted during theuplink period 325. One or more uplink grants for the uplink transmissionmay be transmitted and received during the downlink period 320. Prior totransmitting an uplink transmission during the uplink period 325, a UEmay perform a LBT procedure 330 (e.g., a CCA procedure or ECCAprocedure) at a time t1, prior to the uplink period 325. The LBTprocedure 330 may be performed to contend for access to the shared radiofrequency spectrum band for an uplink transmission during the uplinkperiod 325. When the UE wins contention for access to the shared radiofrequency spectrum band for the uplink transmission, the UE may transmitto the base station during a number of TTIs (e.g., during a number of Usubframes). When the UE loses contention for access to the shared radiofrequency spectrum band for the uplink transmission, the UE may nottransmit during the uplink period 325, and may have to delaycommunication with the base station until a subsequent uplink period(e.g., a subsequent uplink period for which the UE wins contention foraccess to the shared radio frequency spectrum band). FIG. 3 assumes theUE wins contention for access to the shared radio frequency spectrumband for an uplink transmission during the uplink period 325.

In some examples, the base station may transmit, and the UE may receive,information indicative of at least one type of LBT procedure to performfor the uplink transmission. The information may be transmitted/receivedprior to performance of the LBT procedure 330. In some examples, theinformation indicative of the at least one type of LBT procedure toperform for the uplink transmission may indicate whether a duration ofthe uplink transmission is within the MCOT 315 for which the sharedradio frequency spectrum band was reserved by the base station. In someexamples, the information indicative of the at least one type of LBTprocedure to perform for the uplink transmission may indicate a type ofLBT procedure to perform prior to transmitting the uplink transmission.In some examples, the indication of whether the duration of the uplinktransmission is within the MCOT 315, or the indication of the type ofLBT procedure to perform prior to transmitting the uplink transmission,may be transmitted/received as at least one bit in an uplink grant forthe uplink transmission.

In some examples, the information indicative of the at least one type ofLBT procedure to perform for the uplink transmission may indicate aduration of a portion of the MCOT 315 for which the shared radiofrequency spectrum band is reserved by the base station and availablefor uplink transmissions (e.g., the portion of the MCOT 315 followingthe downlink period 320). In some examples, the indication of theduration of the portion of the MCOT 315 for which the shared radiofrequency spectrum band is reserved by the base station and availablefor uplink transmissions may be signaled in a common physical downlinkcontrol channel (CPDCCH) received by more than one (or all) UEs. A UEthat receives the duration of the portion of the MCOT 315 for which theshared radio frequency spectrum band is reserved by the base station andavailable for uplink transmissions may use the duration of the portionof the MCOT and a duration of an uplink transmission to determinewhether the duration of the uplink transmission is within the MCOT 315.

In some examples, a UE receiving the information indicative of the atleast one type of LBT procedure to perform for the uplink transmissionmay use the information to determine that an uplink transmission of theUE has a duration that is within the MCOT 315. The UE may also determinethat, because the uplink transmission has a duration that is within theMCOT 315, the LBT procedure 330 may be a shorter LBT procedure (e.g., a25 microsecond (μs) LBT procedure).

In some examples, the transmission opportunity 310 may include more thanone DL-UL transition (e.g., more than one instance of a downlink period320 followed by an uplink period 325).

FIG. 4 shows a timeline 400 of wireless communications between a basestation and number of UEs, in accordance with various aspects of thepresent disclosure. The wireless communications may occur in a sharedradio frequency spectrum band. The shared radio frequency spectrum bandmay include a radio frequency spectrum band available for Wi-Fi use, aradio frequency spectrum band available for use by different radioaccess technologies, or a radio frequency spectrum band available foruse by multiple MNOs in an equally shared or prioritized manner. In someexamples, the base station(s) and UE(s) that communicate in the sharedradio frequency spectrum band may be examples of aspects of the basestations 105, 205, or 205-a and UEs 115, 215, 215-a, or 215-b asdescribed with reference to FIG. 1 or 2.

In some examples, a base station may perform a LBT procedure 405 (e.g.,a CCA procedure or ECCA procedure) at a time t0, prior to a transmissionopportunity 410. The LBT procedure 405 may be performed to contend foraccess to the shared radio frequency spectrum band during thetransmission opportunity 410. The transmission opportunity 410 may beassociated with a MCOT 415. When the base station wins contention foraccess to the shared radio frequency spectrum band for the transmissionopportunity 410, the base station may transmit to one or more UEs duringa number of TTIs (e.g., during a number of D subframes). The basestation may also schedule uplink transmissions from one or more UEsduring a number of TTIs (e.g., during a number of U subframes). When thebase station loses contention for access to the shared radio frequencyspectrum band for the transmission opportunity 410, the base station maynot transmit or schedule uplink transmissions during the transmissionopportunity 410, and may have to delay communication with one or moreUEs until a subsequent transmission opportunity (e.g., a subsequenttransmission opportunity for which the base station wins contention foraccess to the shared radio frequency spectrum band). FIG. 4 assumes thebase station wins contention for access to the shared radio frequencyspectrum band during the LBT procedure 405.

By way of example, the timeline 400 shows a downlink period 420 followedby an uplink period 425. The uplink period 425 may extend past an end ofthe transmission opportunity 410. A downlink transmission may betransmitted during the downlink period 420, and an uplink transmissionmay be transmitted during the uplink period 425. One or more uplinkgrants for the uplink transmission may be transmitted and receivedduring the downlink period 420. Prior to transmitting an uplinktransmission during the uplink period 425, a UE may perform a LBTprocedure 430 (e.g., a CCA procedure or ECCA procedure) at a time t1,prior to the uplink period 425. The LBT procedure 430 may be performedto contend for access to the shared radio frequency spectrum band for anuplink transmission during the uplink period 425. When the UE winscontention for access to the shared radio frequency spectrum band forthe uplink transmission, the UE may transmit to the base station duringa number of TTIs (e.g., during a number of U subframes). When the UEloses contention for access to the shared radio frequency spectrum bandfor the uplink transmission, the UE may not transmit during the uplinkperiod 425, and may have to delay communication with the base stationuntil a subsequent uplink period (e.g., a subsequent uplink period forwhich the UE wins contention for access to the shared radio frequencyspectrum band). FIG. 4 assumes the UE wins contention for access to theshared radio frequency spectrum band for an uplink transmission duringthe uplink period 425.

In some examples, the base station may transmit, and the UE may receive,information indicative of at least one type of LBT procedure to performfor the uplink transmission. The information may be transmitted/receivedprior to performance of the LBT procedure 430. In some examples, theinformation indicative of the at least one type of LBT procedure toperform for the uplink transmission may indicate whether a duration ofthe uplink transmission is within the MCOT 415 for which the sharedradio frequency spectrum band was reserved by the base station. In someexamples, the information indicative of the at least one type of LBTprocedure to perform for the uplink transmission may indicate a type ofLBT procedure to perform prior to transmitting the uplink transmission.In some examples, the indication of whether the duration of the uplinktransmission is within the MCOT 415, or the indication of the type ofLBT to perform prior to transmitting the uplink transmission, may betransmitted/received as at least one bit in an uplink grant for theuplink transmission.

In some examples, the information indicative of the at least one type ofLBT procedure to perform for the uplink transmission may indicate aduration of a portion of the MCOT 415 for which the shared radiofrequency spectrum band is reserved by the base station and availablefor uplink transmissions (e.g., the portion of the MCOT 415 followingthe downlink period 420). In some examples, the indication of theduration of the portion of the MCOT 415 for which the shared radiofrequency spectrum band is reserved by the base station and availablefor uplink transmissions may be signaled in a CPDCCH received by morethan one (or all) UEs. A UE that receives the duration of the portion ofthe MCOT 415 for which the shared radio frequency spectrum band isreserved by the base station and available for uplink transmissions mayuse the duration of the portion of the MCOT 415 and a duration of anuplink transmission to determine whether the duration of the uplinktransmission is within the MCOT 415.

In some examples, a UE receiving the information indicative of the atleast one type of LBT procedure to perform for the uplink transmissionmay use the information to determine that an uplink transmission of theUE has a duration that exceeds the MCOT 415. The UE may also determinethat, because the uplink transmission has a duration that exceeds theMCOT 415, the LBT procedure 430 may be a shorter type of LBT procedure(e.g., a 25 LBT procedure), but a longer type of LBT procedure (e.g., acategory 4 (CAT 4) LBT procedure) needs to be performed beforecontinuing the uplink transmission past the end of the MCOT 415.Alternatively, the UE may determine that, because the uplinktransmission has a duration that exceeds the MCOT 415, the LBT procedure430 may need to be a longer type of LBT procedure (e.g., a CAT 4 LBTprocedure). A longer LBT procedure may be performed using parameters fora LBT priority class. When performing a LBT procedure associated with aLBT priority class, the UE may continue to transmit as long as allowedby the parameters of the LBT priority class (subject to schedulingconstraints of the base station).

In some examples, the transmission opportunity 410 may include more thanone DL-UL transition (e.g., more than one instance of a downlink period420 followed by an uplink period 425).

In some examples, the LBT procedure 305 or 405 performed by the basestation as described with reference to FIGS. 3 and 4 may be performedfor multiple carriers included in a multiple-carrier transmissionopportunity. Similarly, the LBT procedure 330 or 430 performed by the UEas described with reference to FIGS. 3 and 4 may be performed formultiple carriers included in a multiple-carrier transmissionopportunity.

In some examples, a UE may perform a LBT procedure during a contentionwindow having a contention window size. When a UE performs a LBTprocedure to contend for access to a channel of a shared radio frequencyspectrum band, but does not gain access to the shared radio frequencyspectrum band, the contention window size may be adjusted and the UE mayperform the LBT procedure again based at least in part on the updatedcontention window size.

A contention window size used by a UE to contend for access to a sharedradio frequency spectrum band (e.g., a contention window size for a Cat4 LBT procedure) may be determined (e.g., initialized, adjusted, orreset) by a network access device, a UE, or a combination thereof. Insome examples, a contention window size may be determined based at leastin part on the transmissions made in or for, or the transmissionsreceived in or for, a reference scheduled transmission burst including aplurality of contiguous TTIs (e.g., uplink TTIs or uplink subframes)transmitted/received over a shared radio frequency spectrum band. Insome examples, a contention window size may be determined based at leastin part on the transmissions made in or for, or the transmissionsreceived in or for, a reference TTI of a reference scheduledtransmission burst transmitted over a shared radio frequency spectrumband.

In an example in which a network access device determines a contentionwindow size usable by a UE, the UE may begin transmitting TTIs (e.g.,uplink TTIs or uplink subframes) of a reference scheduled transmissionburst over a shared radio frequency spectrum band, and the networkaccess device may monitor for a first reference signal (e.g., a soundingreference signal (SRS) or demodulation reference signal (DMRS)) receivedfrom the UE in the reference scheduled transmission burst. Upondetecting the first reference signal, the network access device mayidentify a reference TTI in which the first reference signal isreceived. The network access device may then determine one or more ofthe following: whether a transport block (TB) on a scheduled physicaluplink shared channel (PUSCH) of the reference TTI is correctly decoded;whether aperiodic channel state information (CSI) without a PUSCH istriggered on the reference TTI; whether a physical uplink controlchannel (PUCCH) with a cyclic redundancy check (CRC) is scheduled in thereference TTI and correctly decoded; whether a random access preamblescheduled on a physical random access channel (PRACH) in the referenceTTI (e.g., a PRACH Msg 1) is correctly decoded; whether a firstscheduled uplink transmission associated with a random access procedureand received in the reference TTI (e.g., a PRACH Msg 3) is correctlydecoded, or a combination thereof.

In response to correctly decoding a TB on a scheduled PUSCH of thereference TTI, the network access device may reset the contention windowsize used by the UE (e.g., to an initial contention window size or asmallest contention window size). In response to determining aperiodicCSI without a PUSCH is triggered on the reference TTI, the networkaccess device may not update the contention window size. In response tocorrectly decoding a PUCCH with a CRC scheduled in the reference TTI,the network access device may reset the contention window size. Inresponse to correctly decoding a random access preamble scheduled on aPRACH in the reference TTI, the network access device may reset thecontention window size. In response to correctly decoding a firstscheduled uplink transmission associated with a random access procedure,which first scheduled uplink transmission is received in the referenceTTI, the network access device may reset the contention window size.Otherwise, the network access device may increase the contention windowsize to a next highest value for all LBT priority classes. The networkaccess device may transmit an indication of the determined contentionwindow size to the UE.

A potential advantage of determining the contention window size used bya UE at a network device is a reduction in overhead at the UE and anability to determine the contention window size based at least in parton the network access device's success in receiving and correctlydecoding transmissions of the UE.

In an example in which a UE determines a contention window size used bythe UE, the UE may receive at least one uplink grant for a referencescheduled transmission burst including a plurality of contiguous TTIs(e.g., uplink TTIs or uplink subframes) transmitted over a shared radiofrequency spectrum band. In some examples, the UE may receive all of theuplink grants for the reference scheduled transmission burst. In otherexamples, the UE may not receive all of the uplink grants for thereference scheduled transmission burst. At least a first uplink grantmay include a first indication that the uplink grant is associated witha first scheduled TTI of the reference scheduled transmission burst, asecond indication of a position of the first scheduled TTI within thereference scheduled transmission burst (e.g., an indication that thefirst scheduled TTI is associated with a TTI number that is two lessthan the number of the TTI scheduled by the current uplink grant), or acombination thereof. In some examples, each uplink grant for thereference scheduled transmission burst may include an indication of theposition of the first scheduled TTI of the reference scheduledtransmission burst.

The UE may transmit during at least one TTI of the reference scheduledtransmission burst, beginning with a first transmission TTI. The firsttransmission TTI may or may not coincide with the first scheduled TTI,depending on whether the UE received and correctly decoded the uplinkgrant for the first scheduled TTI.

A network access device may monitor for TTIs of the reference scheduledtransmission burst and identify a first TTI of the reference scheduledtransmission burst in which the network access device correctly decodesat least one TB transmitted by the UE. This first TTI may be identified(e.g., by the network access device) as a reference TTI of the referencescheduled transmission burst. Alternatively, the network access devicemay identify the reference TTI as a first TTI of the reference scheduledtransmission burst in which the network access device correctly decodesat least one of: a PUCCH with a CRC; a random access preamble scheduledon a PRACH (e.g., a PRACH Msg 1); a first scheduled uplink transmissionassociated with a random access procedure (e.g., a PRACH Msg 3). Thenetwork access device may transmit an indication of the reference TTI tothe UE. In some examples, the indication of the reference TTI may be anindication relative to the first scheduled TTI. When the network accessdevice does not correctly decode at least one TB transmitted by the UE,the network access device may, in some examples, indicate to the UE thatno reference TTI was identified.

In response to receiving the indication of the reference TTI, the UE maydetermine a contention window size used by the UE to contend for accessto the shared radio frequency spectrum band. The contention window sizemay be determined based at least in part on a relationship between thefirst scheduled TTI, the reference TTI, and the first transmission TTI.For example, the UE may determine, based at least in part on a firstrelationship between the reference TTI and the first scheduled TTI, andbased at least in part on a second relationship between the firsttransmission TTI and the first scheduled TTI, a third relationshipbetween the first transmission TTI and the reference TTI. When the firsttransmission TTI is determined to be an earlier TTI than the referenceTTI, the UE may increase the contention window size used by the UE. Whenthe first transmission TTI is determined to be a later TTI than thereference TTI, the UE may not update the contention window size. Whenthe first transmission TTI is the reference TTI, the contention windowsize may be reset (e.g., to an initial contention window size or asmallest contention window size).

A potential advantage of determining the contention window size used bya UE at the UE is that both network access device and UE informationregarding transmission activity may be factored into the contentionwindow size determination.

In another example in which a UE determines a contention window sizeused by the UE, the UE may transmit a reference scheduled transmissionburst including a plurality of contiguous TTIs (e.g., uplink TTIs oruplink subframes) over a shared radio frequency spectrum band. The UEmay monitor for HARQ acknowledgement (ACK) for the transmission TTIs,and may identify a first of the TTIs for which a HARQ ACK is received asa reference TTI. The UE may also identify a HARQ process correspondingto the reference TTI. The UE may then monitor for an instance of theHARQ process associated with a TTI subsequent to the reference TTI. Theinstance of the HARQ process may be identified based at least in parton: whether the TTI is within the reference scheduled transmission burstor a subsequent transmission burst, whether the TTI includes aperiodicCSI without a PUSCH, or a combination thereof. In some examples, theidentified instance of the HARQ process may be a first instance of theHARQ process that is transmitted within the reference scheduledtransmission burst and does not include aperiodic CSI without a PUSCH.The UE may determine a contention window size used to contend for accessto the shared radio frequency spectrum band based on a state of a newdata indicator (NDI) associated with the identified instance of the HARQprocess.

As described with reference to FIG. 3 or 4, a network access device mayreserve a shared radio frequency spectrum band for a MCOT aftersuccessfully contending for access to the shared radio frequencyspectrum band. In some examples, the network access device may signal,to a UE, a type of LBT procedure that the UE needs to perform beforetransmitting in a set of one or more TTIs. In some examples, the type ofLBT procedure may include a LBT procedure associated with a smallercontention window size (e.g., a 25 μs single slot LBT procedure) when anuplink transmission begins within a MCOT of the network access device,and a LBT procedure associated with a larger contention window size(e.g., a Cat 4 LBT procedure) when the uplink transmission extendsoutside the MCOT of the network access device. In some examples, thetype of LBT procedure that the UE needs to perform (or needs to haveperformed), if any, may be signaled in each uplink grant. In someexamples, the signaling in an uplink grant may include one bitindicating whether the UE needs to perform a first type of LBT procedureor a second type of LBT procedure. However, a UE may be unable to employpower saving techniques when the type of LBT procedure to be performedis indicated in uplink grants, because the indication is just availableto scheduled UEs.

In addition to, or as an alternative to, signaling a type of LBTprocedure to be performed by a UE in an uplink grant transmitted to theUE, a network access device may indicate a remaining channel occupancytime (RCOT) of the network access device to the UE. The UE may thendetermine, based at least in part on the RCOT, a type of LBT procedureto be performed (or to have been performed) before transmitting in aTTI.

The LBT priority class and/or other parameters that a UE uses toconfigure a Cat 4 LBT procedure may be signaled to the UE by a networkaccess device or determined by the UE. For example, a UE may transmit abuffer status report (BSR) to a network access device, and the networkaccess device may determine, based at least in part on the BSR, a LBTpriority class (or other LBT parameters) for the UE to use whenperforming a Cat 4 LBT procedure. The network access device may thenschedule TTIs and gaps for a shared radio frequency spectrum bandaccording to the determined LBT priority class, and may signal thedetermined LBT priority class (or an associated contention window size)to the UE. The UE may contend for access to the shared radio frequencyspectrum band (e.g., perform a Cat 4 LBT procedure) based at least inpart on the signaled LBT priority class, contention window size, orother LBT parameters. Regardless of the LBT priority class used whenperforming the Cat 4 LBT procedure, the UE may use logical channelprioritization (LCP) when transmitting during the TTI(s) for which theCat 4 LBT procedure was performed. In some examples, the BSR transmittedto the network access device, by the UE, maybe a first type of BSRincluding an indication of an amount of data to be transmitted for eachof a plurality of LBT priority classes. The amount of data to betransmitted for each LBT priority class may be used by the networkaccess device, in some examples, to determine whether scheduling the UEin multiple TTIs would lead to the UE likely transmitting dataassociated with different LBT priority classes in different TTIs. Insome examples, the network access device may determine the LBT priorityclass to be used by the UE based on the amounts of data that the UE hasbuffered for different LBT priority classes, or the network accessdevice may determine different LBT priority classes to be performed bythe UE for different TTIs in which the UE is scheduled to transmit.

Instead of signaling a determined LBT priority class (or other LBTparameters) to a UE, a network access device may receive a BSR from a UEand determine, based at least in part on the BSR, a LBT priority class(or other LBT parameters) that the UE is likely to use when performing aCat 4 LBT procedure. The network access device may then schedule TTIsand gaps for a shared radio frequency spectrum band according to thedetermined LBT priority class, and may optionally signal, to the UE, aLBT priority class boundary (or an associated contention window sizeboundary). The LBT priority class boundary may be, for example, ahighest LBT priority class usable by the UE, a lowest LBT priority classusable by the UE, or a combination thereof. Independently from the LBTpriority class determination made by the network access device, or basedat least in part on the LBT priority class boundary signaled by thenetwork access device, the UE may select a LBT priority class forperforming a Cat 4 LBT procedure. The UE's selection of a LBT priorityclass may be based at least in part on a type of data to be transmittedover a shared radio frequency spectrum band by the UE and/or on a numberof TTIs in which the UE is scheduled. The UE may contend for access tothe shared radio frequency spectrum band (e.g., perform a Cat 4 LBTprocedure) based at least in part on the selected LBT priority class.Regardless of the LBT priority class used when performing the Cat 4 LBTprocedure, the UE may use LCP when transmitting during the TTI(s) forwhich the Cat 4 LBT procedure was performed.

In some examples, a network access device may signal (e.g., in a firstuplink grant) that a UE should perform a first LBT procedure inaccordance with a first LBT priority class before transmitting in afirst set of one or more TTIs over a shared radio frequency spectrumband, but the UE may not win contention for access to a shared radiofrequency spectrum band for the first set of one or more TTIs. Thenetwork access device may then signal (e.g., in a second uplink grant)that the UE should perform a second LBT procedure in accordance with asecond LBT priority class before transmitting in a second set of one ormore TTIs over the shared radio frequency spectrum band. In someexamples, the UE may perform the second LBT procedure without regard tothe LBT state at the (unsuccessful) conclusion of the first LBTprocedure. In other examples, the UE may perform the second LBTprocedure based at least in part on the LBT state at the conclusion ofthe first LBT procedure. For example, when the first LBT priority classand the second LBT priority class are the same LBT priority class, theUE may initialize the second LBT procedure based at least in part on theLBT state at the conclusion of the first LBT procedure (e.g., a CCA slotcountdown counter for the second LBT procedure may be initialized to areduced value, if any, corresponding to the terminal value of the CCAslot countdown counter used for the first LBT procedure). When the firstLBT priority class and the second LBT priority class are different LBTpriority classes, the UE may initialize the second LBT procedure basedat least in part on an adjustment to the LBT state at the conclusion ofthe first LBT procedure (e.g., an adjustment based on a differencebetween the first LBT priority class and the second LBT priority class).For example, consider a scenario in which the first LBT priority classis lower than the second LBT priority class, the first LBT priorityclass has a defer time of 3 CCA slots (after 16 μs) and a 7 CCA slotcountdown counter, and the CCA slot countdown counter was interruptedonce (leaving a defer time of 2 CCA slots). In this scenario, the LBTstate associated with the first LBT procedure may be adjusted, based ona second LBT priority class associated with a defer time of 2 CCA slots,to a defer time of 2 CCA slots and a 9 CCA slot countdown timer. In ascenario in which the first LBT priority class is higher than the secondLBT priority class, a UE may track how many CCA slots are successfullycleared after each defer time (e.g., by tracking CCA clearance in eachCCA slot).

When a transmission opportunity (TxOP) contains downlink TTIs and uplinkTTIs, the contention window size used by a network access device tocontend for access to a shared radio frequency spectrum band may bedetermined (e.g., initialized, adjusted, reset) based at least in parton feedback (e.g., physical downlink shared channel (PDSCH) HARQACK/NACK feedback) received from one or more UEs for a downlinkreference TTI of the TxOP. Alternatively, the contention window size maybe determined based at least in part on feedback (e.g., PDSCH HARQACK/NACK feedback) received from one or more UEs for the downlinkreference TTI, and also based at least in part on at least one uplinktransmission received in an uplink TTI scheduled in the downlinkreference TTI. For example, the contention window size may be based atleast in part on a success or failure of decoding at least one channelscheduled in the uplink TTI. In some examples, the success or failure ofdecoding the at least one channel may be based at least in part onACK/NACK feedback for the at least one channel. In some examples, the atleast one channel may include a PUSCH, a PUCCH, or a PRACH.

Before transmitting a multi-carrier transmission over a shared radiofrequency spectrum band, a UE may perform a LBT procedure for one ormore carriers in a plurality of carriers allocated for the multi-carriertransmission. In some examples, a UE may receive scheduling informationfor an uplink transmission to be made over a plurality of carriers of ashared radio frequency spectrum band, and may perform a separate LBTprocedure (e.g., a separate Cat 4 LBT procedure) for each carrier. Aseparate CCA slot countdown counter may be maintained for each LBTprocedure. In other examples, a UE may perform a separate LBT procedure(e.g., a separate Cat 4 LBT procedure) for each carrier on which anuplink transmission of the UE is scheduled, and maintain a joint CCAslot countdown counter for each LBT procedure. In further examples, a UEmay perform a first type of LBT procedure (e.g., a Cat 4 LBT procedure)for one carrier of a plurality of carriers on which an uplinktransmission of the UE is scheduled, and may perform a second type ofLBT procedure for each other carrier in the plurality of carriers. Insome examples, the second type of LBT procedure may be associated with asmaller contention window size than the first type of LBT procedure. Forexample, the second type of LBT procedure may be associated with a 25LBT procedure. In some examples, the carrier for which the first type ofLBT procedure is performed may be identified based at least in part onan indication received from a network access device. The indication maybe received, for example, in uplink downlink control information (DCI)for the identified carrier, or in uplink DCI for each carrier of theplurality of carriers on which the UE is scheduled. When a networkaccess device transmits the indication on each carrier on which a UE isscheduled, the UE may be more likely to receive the indication (andconversely, when a network access device transmits the indication onjust the carrier identified by the indication, the UE may be less likelyto receive the indication (e.g., because the UE is more likely toreceive uplink DCI for at least one of a plurality of carriers than itis likely to receive uplink DCI for one particular carrier). In otherexamples, the carrier for the first type of LBT procedure is performedmay be identified by the UE independently. In some examples, a UE thatdoes not receive a network access device's indication of a carrier forwhich to perform the first type of LBT procedure may, as a fallback,independently identify a carrier for which to perform the first type ofLBT procedure. In all of the above examples, the UE may transmit atransmission (and in some examples, a multi-carrier transmission) oneach of the plurality of carriers on which the UE is scheduled and winscontention for access.

In some examples, a UE may use the same energy detection threshold forall types of LBT procedures. In other examples, a UE may use differentenergy detection thresholds for different types of LBT procedures (e.g.,a first energy detection threshold for a first type of LBT procedure,and a second energy detection threshold for a second type of LBTprocedure). For example, a UE may perform a 25 μs LBT procedure using a−72 dBm energy detection threshold (or a same energy detection thresholdused by a network access device when performing a LBT procedure prior totransmitting on a downlink), and may perform a Cat 4 LBT procedure usinga different (e.g., lower) energy detection threshold (e.g., an energydetection threshold lower than −72 dBm).

In some examples, a UE may begin performing a LBT procedure uponreceiving an uplink grant, or in a next TTI following receipt of anuplink grant, or at a next symbol period boundary or next CCA slotboundary following receipt of an uplink grant. In some examples, the UEmay begin performing the LBT procedure regardless of whether the UE iscurrently receiving a transmission. In other examples, the UE may beprohibited from performing a LBT procedure, or prohibited from updatinga countdown timer associated with the performance of a LBT procedure,while the UE is receiving a transmission (e.g., from a network accessdevice or another device). The UE may also or alternatively beprohibited from performing a LBT procedure, or updating a countdowntimer associated with the performance of a LBT procedure, during a TTIin which the UE receives a transmission (e.g., from a network accessdevice or another device). For example, a UE may receive (e.g., from anetwork access device) an indication that the UE cannot update acountdown counter associated with performance of a LBT procedure duringa TTI in which the UE receives a transmission. When the UE thendetermines the UE is receiving a transmission during a TTI, the UE mayrefrain from at least one of: performing a LBT procedure during the TTI,updating a countdown counter associated with performance of the LBTprocedure, or a combination thereof. In some examples, refraining fromupdating a countdown counter may include updating the countdown counterduring a TTI, but rolling back the countdown counter so that a value ofthe countdown counter at the end of the TTI is the same as the value ofthe countdown counter at the beginning of the TTI. In some examples, theindication that the UE cannot update the countdown counter may bereceived in at least one of RRC signaling, a system information block(SIB), DCI, or a combination thereof.

In some examples, frequency resources may be allocated to a PUSCH ininterlaced sets. For example, a set of 100 resource blocks (RBs)spanning a system bandwidth may be divided into 10 interlaces, with eachinterlace allocated 10 non-contiguous RBs in the frequency domain. Whenallocating a number of interlaces to a PUSCH, the interlaces may beallocated in a number of ways. For example, a bitmap may include one bitper interlace (i.e., a total of 10 bits), and a bit corresponding to aninterlace may be set when the interlace is allocated and cleared whenthe interlace is not allocated. Alternatively, a number of interlacesmay be allocated to a PUSCH using a resource indication value (MV). A MVfor allocating one or more of 10 interlaces to a PUSCH may include 6bits, which bits may indicate a first interlace and number of interlacescontiguous with the first interlace that are allocated to a PUSCH.Alternatively, a number of interlaces may be allocated to a PUSCH usingan extended length MV. The extended length MV may include one or moreadditional bits, which additional bits enable the allocation of somecustom interlace combinations to a PUSCH. The custom interlacecombinations may include interlace combinations that anticipate theallocation of a PUCCH or PRACH that overlaps a PUSCH in the frequencydomain.

When a PUCCH or PRACH is allocated resources that overlap the resourcesallocated to a PUSCH in the frequency domain, or when a PUSCH isallocated a custom interlace combination, the modulation and codingscheme (MCS) for the PUSCH may be rate-matched around the PUCCH orPRACH. A PUSCH may also be rate-matched around a SRS. However, in thecase of a multi-TTI grant in which a MCS is indicated for all of theTTIs in the grant, the MCS cannot be rate-matched around differentchannels or signals transmitted in different TTIs. In some examples, oneor more MCS offsets may be signaled to a UE to enable rate-matchingaround channels or signals that reduce, in a TTI, the number of resourceelements (REs) available for transmission of a PUSCH. In some examples,one or more TBS offsets or other transmission parameters may also oralternatively be signaled to a UE.

In one example, a network access device may transmit (and a UE mayreceive) an indication of a transmission parameter (e.g., a MCS or TBS)for an uplink transmission to be made over a shared radio frequencyspectrum band during at least one TTI. The UE may identify the contentof the uplink transmission in each TTI, and may optionally scale thereceived transmission parameter (e.g., the MCS or TBS) for a TTI havinga content that differs (or differs enough) from a nominal content of aTTI. In some examples, the nominal content of a TTI may include a PUSCH,and the content of a TTI for which the transmission parameter may bescaled may include, for example, at least one of: a number of REs thatdiffers (or differs enough) from a number of REs in the nominal content,a number of punctured symbol periods (e.g., for a LBT procedure,transmission of a SRS, etc.), a PUCCH, a PRACH, a SRS, or a combinationthereof. Upon identifying a TTI having a content that differs (ordiffers enough) from the nominal content of a TTI, the UE may scale atransmission parameter for the identified TTI. In some examples, scalingthe transmission parameter may include switching to a fixed alternativetransmission parameter. In some examples, scaling the transmissionparameter may include computing an alternative transmission parameterbased at least in part on a comparison of the identified content to thenominal content. A UE may or may not scale a transmission parameter, ormay or may not scale a transmission parameter in the same way, whenperforming a retransmission of a PUSCH.

In some examples, HARQ ACK feedback for a PDSCH received on a carrier ina shared radio frequency spectrum band may be transmitted on a PUCCH ona carrier in a dedicated radio frequency spectrum band. When a PUCCHtransmitted on a carrier in a dedicated radio frequency spectrum band isnot available, transmission of the HARQ ACK feedback to a network accessdevice may be delayed. In some examples, it may be undesirable totransmit or receive HARQ ACK feedback on a carrier in a shared radiofrequency spectrum band. In other examples, it may not be undesirable totransmit or receive HARQ ACK feedback on a carrier in a shared radiofrequency spectrum band. Thus, in some examples, a network access devicemay transmit, to a UE, a configuration for reporting HARQ ACK feedbackfor a carrier in a shared radio frequency spectrum band. In someexamples, the configuration may include a configuration in one of: afirst mode in which the UE transmits HARQ ACK feedback on a PUCCH on acarrier in a dedicated radio frequency spectrum band, or a second modein which the UE selects to transmit HARQ ACK feedback on the PUCCH onthe carrier in the dedicated radio frequency spectrum band or on a PUSCHon the carrier for which the HARQ ACK feedback is provided. Theconfiguration for reporting HARQ ACK feedback may be transmitted, forexample, using RRC signaling.

In some examples, a UE may report periodic CSI for a first carrier in ashared radio frequency spectrum band on a second carrier in a dedicatedradio frequency spectrum band, and may be prohibited from reportingperiodic CSI for the first carrier on the first carrier (or on a PUSCHon the first carrier). In some examples, a UE may report aperiodic CSIfor carriers in a dedicated radio frequency spectrum band and carriersin a shared radio frequency spectrum band on a carrier in the sharedradio frequency spectrum band, with aperiodic CSI being dropped when aUE does not win contention for access to the shared radio frequencyspectrum band for a TTI in which the aperiodic CSI is to be reported.Aperiodic CSI may also be dropped when a TTI in which the aperiodic CSIis to be reported does not include a PUSCH on which to report theaperiodic CSI. To enable a UE's transmission of aperiodic CSI without aPUSCH, a network access device may in some examples transmit, to a UE,an indication of an invalid PUSCH resource allocation for a TTI over ashared radio frequency spectrum band. The invalid PUSCH resourceallocation may signal to the UE that the UE can transmit aperiodic CSIin the TTI despite a PUSCH not being scheduled in the TTI. In someexamples, the invalid PUSCH resource allocation may include an invalidfrequency interlace combination (e.g., 7 interlaces) with a designatedbit pattern for a redundancy version (RV) and a NDI. In some examples,the network access device may signal a HARQ ID for the transmission ofthe aperiodic CSI without a PUSCH. In some examples, the signaled HARQID may be considered invalid (i.e., because a PUSCH will not betransmitted in the TTI).

To trigger a transmission of aperiodic CSI without a PUSCH, TTItransmitted on over a shared radio frequency spectrum band, and in ascenario in which the TTI is scheduled by a multi-TTI grant, a networkaccess device may indicate, to a UE, that just the first TTI scheduledby the multi-TTI grant is active. In response to receiving theindication that just the first TTI is active, the UE may transmitaperiodic CSI without a PUSCH in the first TTI.

To trigger the transmission of aperiodic CSI without a PUSCH, in a TTItransmitted on over a shared radio frequency spectrum band, and in ascenario in which the TTI is scheduled by a multi-TTI grant, a networkaccess device may transmit, to the UE, a code point associated withtransmission of aperiodic CSI over a shared radio frequency spectrumband, in a TTI scheduled without a PUSCH. When the network access devicedetermines the UE should transmit aperiodic CSI in a TTI without aPUSCH, in which the TTI is scheduled by a multi-TTI grant, the networkaccess device may reference the code point in the multi-TTI grant. TheUE may then transmit aperiodic CSI without a PUSCH in the TTI, inaccordance with the code point.

In some examples, the transmission of aperiodic CSI without a PUSCH, ina TTI scheduled in a multi-TTI grant and transmitted over a shared radiofrequency spectrum band, may not be allowed.

Before transmitting an aperiodic SRS without a PUSCH in a TTI of ashared radio frequency spectrum band, a UE may perform a LBT proceduresuch as a Cat 3 LBT procedure or a Cat 4 LBT procedure. In someexamples, the UE may perform a Cat 3 LBT procedure, and may select acontention window size for performing the Cat 3 LBT procedure. In someexamples, the contention window sizes from which the UE may select acontention window size may be limited (e.g., to a contention window sizeof 3 CCA slots or 7 CCA slots). In other examples, the UE may perform aCat 3 LBT procedure based on a predetermined or signaled contentionwindow size (e.g., a contention window size of 7 CCA slots). In someexamples, the defer time associated with a Cat 3 LBT procedure performedby a UE, prior to transmission of an aperiodic SRS without a PUSCH, maybe set to a defer time associated with a highest LBT priority class.

In some examples, a UE may perform a Cat 4 LBT procedure prior totransmitting an aperiodic SRS without a PUSCH in a TTI of a shared radiofrequency spectrum band. Because there is no ACK/NACK of SRStransmissions, there may be no information on which to base anadjustment of a contention window size associated with a Cat 4 LBTprocedure. In some examples, the contention window size associated withthe Cat 4 LBT procedure may be adjusted randomly, by the UE. In otherexamples, the contention window size associated with the Cat 4 LBTprocedure may be adjusted by the network access device, based at leastin part on an expected frequency of SRS requests made by the networkaccess device. In some examples, the determined contention window sizemay be larger when the network access device expects to make a greaternumber of SRS requests. The network access device may signal thedetermined contention window size to the UE in RRC signaling or DCI.

In some examples, a SRS may be triggered in a TTI of a shared radiofrequency spectrum band in which a PUSCH is scheduled, but because theSRS is triggered and the PUSCH is scheduled using different mechanisms,the scheduling of the PUSCH may not leave a gap for transmitting theSRS. For example, a SRS may be triggered by DCI in a TTI n, and a PUSCHmay be scheduled in the TTI n by an uplink grant transmitted/received inan earlier TTI. When the scheduling of the PUSCH does not leave a gapfor the SRS, a UE may transmit, during the TTI, one of: the PUSCH ratematched around the SRS, the PUSCH punctured by the SRS, the PUSCHwithout the SRS, or the SRS without the PUSCH.

In some examples, a network access device may not allocate resources totransmit a PRACH over a shared radio frequency spectrum band. A UE mayoperate effectively without a PRACH, for example, in scenarios in whichthere is limited separation between the network access devices that arerespectively associated with one or more carriers in a dedicated radiofrequency spectrum band and one or more carriers in a shared radiofrequency spectrum band (e.g., when the network access devices are inthe same timing advance group (TAG)). In other scenarios, the absence ofa PRACH may make it more difficult for a UE to effectively initialize atiming advance (TA) or uplink transmit power. In these and otherscenarios, a network access device may transmit an indication of adefault initial TA for a carrier of a shared radio frequency spectrumband. In some examples, the default initial TA may be a TA of a carrierin a dedicated radio frequency spectrum band, with the carrier in thededicated radio frequency spectrum band being in a same TAG as thecarrier in the shared radio frequency spectrum band. Alternatively, thedefault initial TA may be a static initial TA (e.g., “0”).

A network access device may also transmit an indication of a defaultuplink transmit power. In some examples, the default initial transmitpower may be a maximum uplink transmit power, and a UE that receives theindication of the maximum uplink transmit power may initially transmitat the maximum uplink transmit power, and lower the uplink transmitpower in steps when needed. In some examples, the default initialtransmit power may be included in a code point transmitted to a UE. Forexample, a plurality of code points indicating different uplink transmitpower adjustment steps may be transmitted to a UE, in addition to a codepoint providing the indication of the default uplink transmit power. Insome examples, the indication of the default uplink transmit power maybe transmitted to a UE in at least one of: a SIB, a RRC configuration,or a combination thereof.

FIG. 5 shows a block diagram 500 of an apparatus 515 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The apparatus 515 may be an example of aspects of one ormore of the UEs 115, 215, 215-a, or 215-b as described with reference toFIG. 1 or 2. The apparatus 515 may also be or include a processor. Theapparatus 515 may include a receiver 510, a wireless communicationmanager 520, or a transmitter 530. Each of these components may be incommunication with each other.

The components of the apparatus 515 may, individually or collectively,be implemented using one or more application-specific integratedcircuits (ASICs) adapted to perform some or all of the applicablefunctions in hardware. Alternatively, the functions may be performed byone or more other processing units (or cores), on one or more integratedcircuits. In other examples, other types of integrated circuits may beused (e.g., Structured/Platform ASICs, Field Programmable Gate Arrays(FPGAs), a System-on-Chip (SoC), and/or other types of Semi-Custom ICs),which may be programmed in any manner known in the art. The functions ofeach component may also be implemented, in whole or in part, withinstructions embodied in a memory, formatted to be executed by one ormore general or application-specific processors.

In some examples, the receiver 510 may include at least one radiofrequency (RF) receiver, such as at least one RF receiver operable toreceive transmissions over a dedicated radio frequency spectrum band(e.g., a radio frequency spectrum band licensed to particular users forparticular uses) or a shared radio frequency spectrum band (e.g., aradio frequency spectrum band available for Wi-Fi use, a radio frequencyspectrum band available for use by different radio access technologies,or a radio frequency spectrum band available for use by multiple MNOs inan equally shared or prioritized manner). In some examples, thededicated radio frequency spectrum band or the shared radio frequencyspectrum band may be used for LTE/LTE-A communications, as described,for example, with reference to FIG. 1, 2, 3, or 4. The receiver 510 maybe used to receive various types of data or control signals (i.e.,“data” or transmissions) over one or more communication links of awireless communication system, such as one or more communication linksof the wireless communication system 100 or 200 as described withreference to FIG. 1 or 2. The communication links may be establishedover the dedicated radio frequency spectrum band or the shared radiofrequency spectrum band.

In some examples, the transmitter 530 may include at least one RFtransmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum band or the shared radiofrequency spectrum band. The transmitter 530 may be used to transmitvarious types of data or control signals (i.e., “data” or transmissions)over one or more communication links of a wireless communication system,such as one or more communication links of the wireless communicationsystem 100 or 200 as described with reference to FIG. 1 or 2. Thecommunication links may be established over the dedicated radiofrequency spectrum band or the shared radio frequency spectrum band.

In some examples, the wireless communication manager 520 may be used tomanage one or more aspects of wireless communication for the apparatus515. In some examples, part of the wireless communication manager 520may be incorporated into or shared with the receiver 510 or thetransmitter 530. In some examples, the wireless communication manager520 may include a downlink transmission reception manager 535, aspectrum contention manager 540, a BSR manager 545, a SRS manager 550, aCSI manager 555, an uplink transmission manager 560, or a HARQ manager.

The downlink transmission reception manager 535 may be used, forexample, to receive and process downlink transmissions, as described,for example, with reference to FIG. 13 or 21.

The spectrum contention manager 540 may be used, for example, toconfigure, or to assist in configuring, one or more types of LBTprocedure to be performed by the apparatus 515 to contend for access toa shared radio frequency spectrum band (e.g., to a channel of a sharedradio frequency spectrum band), as described, for example, withreference to FIG. 10, 11, 14, 15, 16, 18, 20, or 21.

The BSR manager 545 may be used, for example, to configure and transmitone or more types of BSR, as described, for example, with reference toFIG. 14 or 15.

The SRS manager 550 may be used, for example, to allocate resources toand transmit SRS transmissions, including aperiodic SRS transmissions,as described, for example, with reference to FIG. 29.

The CSI manager 555 may be used, for example, to acquire and transmitCSI transmissions, including aperiodic CSI transmissions, as described,for example, with reference to FIG. 25 or 27.

The uplink transmission manager 560 may be used, for example, to receivescheduling information for, and transmit, uplink transmissions, asdescribed, for example, with reference to FIG. 10, 11, 12, 16, 18, 22,27, 29, or 30.

The HARQ manager may be used, for example, to manage HARQ processes(e.g., to transmit HARQ feedback, process HARQ feedback, perform HARQretransmissions, etc.), as described, for example, with reference toFIG. 11, 23, or 25.

FIG. 6 shows a block diagram 600 of an apparatus 605 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The apparatus 605 may be an example of aspects of one ormore of the base stations 105, 205, or 205-a as described with referenceto FIG. 1 or 2. The apparatus 605 may also be or include a processor.The apparatus 605 may include a receiver 610, a wireless communicationmanager 620, or a transmitter 630. Each of these components may be incommunication with each other.

The components of the apparatus 605 may, individually or collectively,be implemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, a SoC,and/or other types of Semi-Custom ICs), which may be programmed in anymanner known in the art. The functions of each component may also beimplemented, in whole or in part, with instructions embodied in amemory, formatted to be executed by one or more general orapplication-specific processors.

In some examples, the receiver 610 may include at least one RF receiver,such as at least one RF receiver operable to receive transmissions overa dedicated radio frequency spectrum band (e.g., a radio frequencyspectrum band licensed to particular users for particular uses) or ashared radio frequency spectrum band (e.g., a radio frequency spectrumband available for Wi-Fi use, a radio frequency spectrum band availablefor use by different radio access technologies, or a radio frequencyspectrum band available for use by multiple MNOs in an equally shared orprioritized manner). In some examples, the dedicated radio frequencyspectrum band or the shared radio frequency spectrum band may be usedfor LTE/LTE-A communications, as described, for example, with referenceto FIG. 1, 2, 3, or 4. The receiver 610 may be used to receive varioustypes of data or control signals (i.e., “data” or transmissions) overone or more communication links of a wireless communication system, suchas one or more communication links of the wireless communication system100 or 200 as described with reference to FIG. 1 or 2. The communicationlinks may be established over the dedicated radio frequency spectrumband or the shared radio frequency spectrum band.

In some examples, the transmitter 630 may include at least one RFtransmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum band or the shared radiofrequency spectrum band. The transmitter 630 may be used to transmitvarious types of data or control signals (i.e., “data” or transmissions)over one or more communication links of a wireless communication system,such as one or more communication links of the wireless communicationsystem 100 or 200 as described with reference to FIG. 1 or 2. Thecommunication links may be established over the dedicated radiofrequency spectrum band or the shared radio frequency spectrum band.

In some examples, the wireless communication manager 620 may be used tomanage one or more aspects of wireless communication for the apparatus605. In some examples, part of the wireless communication manager 620may be incorporated into or shared with the receiver 610 or thetransmitter 630. In some examples, the wireless communication manager620 may include a network access device spectrum contention manager 635,a UE spectrum contention manager 640, a HARQ manager 645, a SRS manager650, a CSI manager 655, or an uplink transmission manager 660.

The network access device spectrum contention manager 635 may be used,for example, to configure and perform one or more types of LBT procedureto contend for access to a shared radio frequency spectrum band (e.g.,to a channel of a shared radio frequency spectrum band), as described,for example, with reference to FIG. 17.

The UE spectrum contention manager 640 may be used, for example, toconfigure, or to assist in configuring, one or more types of LBTprocedure to be performed by a UE to contend for access to a sharedradio frequency spectrum band (e.g., to a channel of a shared radiofrequency spectrum band), as described, for example, with reference toFIG. 9, 19, or 28.

The HARQ manager 645 may be used, for example, to manage HARQ processes(e.g., to allocate HARQ resources, transmit HARQ feedback, process HARQfeedback, initiate HARQ retransmissions, etc.), as described, forexample, with reference to FIG. 17 or 24.

The SRS manager 650 may be used, for example, to allocate resources to,request, and/or process SRS transmissions, including aperiodic SRStransmissions, as described, for example, with reference to FIG. 28.

The CSI manager 655 may be used, for example, to allocate resources to,request, and/or process CSI transmissions, including aperiodic CSItransmissions, as described, for example, with reference to FIG. 26.

The uplink transmission manager 660 may be used, for example, toschedule and receive uplink transmissions, as described, for example,with reference to FIG. 19 or 26.

FIG. 7 shows a block diagram 700 of a UE 715 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The UE 715 may be included or be part of a personal computer(e.g., a laptop computer, a netbook computer, a tablet computer, etc.),a cellular telephone, a PDA, a DVR, an internet appliance, a gamingconsole, an e-reader, etc. The UE 715 may, in some examples, have aninternal power supply (not shown), such as a small battery, tofacilitate mobile operation. In some examples, the UE 715 may be anexample of aspects of one or more of the UEs 115, 215, 215-a, or 215-bas described with reference to FIG. 1 or 2, or aspects of the apparatus515 as described with reference to FIG. 5. The UE 715 may be configuredto implement at least some of the UE or apparatus techniques andfunctions as described with reference to FIG. 1, 2, 3, 4, or 5.

The UE 715 may include a UE processor 710, a UE memory 720, at least oneUE transceiver (represented by UE transceiver(s) 730), at least one UEantenna (represented by UE antenna(s) 740), or a UE wirelesscommunication manager 750. Each of these components may be incommunication with each other, directly or indirectly, over one or morebuses 735.

The UE memory 720 may include random access memory (RAM) or read-onlymemory (ROM). The UE memory 720 may store computer-readable,computer-executable code 725 containing instructions that are configuredto, when executed, cause the UE processor 710 to perform variousfunctions described herein related to wireless communication, including,for example, determining a contention window size for performing a LBTprocedure with respect to a shared radio frequency spectrum band,transmitting an uplink transmission over the shared radio frequencyspectrum band, transmitting aperiodic CSI for a carrier transmitted overthe shared radio frequency spectrum band, transmitting a SRS over acarrier transmitted over the shared radio frequency spectrum band, etc.Alternatively, the computer-executable code 725 may not be directlyexecutable by the UE processor 710 but be configured to cause the UE 715(e.g., when compiled and executed) to perform various of the functionsdescribed herein.

The UE processor 710 may include an intelligent hardware device, e.g., acentral processing unit (CPU), a microcontroller, an ASIC, etc. The UEprocessor 710 may process information received through the UEtransceiver(s) 730 or information to be sent to the UE transceiver(s)730 for transmission through the UE antenna(s) 740. The UE processor 710may handle, alone or in connection with the UE wireless communicationmanager 750, various aspects of communicating over (or managingcommunications over) a dedicated radio frequency spectrum band or ashared radio frequency spectrum band.

The UE transceiver(s) 730 may include a modem configured to modulatepackets and provide the modulated packets to the UE antenna(s) 740 fortransmission, and to demodulate packets received from the UE antenna(s)740. The UE transceiver(s) 730 may, in some examples, be implemented asone or more UE transmitters and one or more separate UE receivers. TheUE transceiver(s) 730 may support communications in the dedicated radiofrequency spectrum band or the shared radio frequency spectrum band. TheUE transceiver(s) 730 may be configured to communicate bi-directionally,via the UE antenna(s) 740, with one or more network access devices, basestations, or apparatuses, such as one or more of the base stations 105,205, or 205-a described with reference to FIG. 1 or 2, or one or more ofthe apparatus 605 as described with reference to FIG. 6. While the UE715 may include a single UE antenna, there may be examples in which theUE 715 may include multiple UE antennas 740.

The UE wireless communication manager 750 may be configured to performor control some or all of the UE or apparatus techniques or functions asdescribed with reference to FIG. 1, 2, 3, 4, or 5 related to wirelesscommunication over the dedicated radio frequency spectrum band or theshared radio frequency spectrum band. For example, the UE wirelesscommunication manager 750 may be configured to support a supplementaldownlink mode (e.g., a licensed assisted access mode), a carrieraggregation mode (e.g., an enhanced licensed assisted access mode), or astandalone mode using the dedicated radio frequency spectrum band or theshared radio frequency spectrum band. The UE wireless communicationmanager 750 may include a UE LTE/LTE-A component for dedicated RFspectrum band 755 configured to handle LTE/LTE-A communications in thededicated radio frequency spectrum band, and a UE LTE/LTE-A componentfor shared RF spectrum band 760 configured to handle LTE/LTE-Acommunications in the shared radio frequency spectrum band. The UEwireless communication manager 750, or portions of it, may include aprocessor, or some or all of the functions of the UE wirelesscommunication manager 750 may be performed by the UE processor 710 or inconnection with the UE processor 710. In some examples, the UE wirelesscommunication manager 750 may be an example of the wirelesscommunication manager 520 as described with reference to FIG. 5.

FIG. 8 shows a block diagram 800 of a base station 805 for use inwireless communication, in accordance with various aspects of thepresent disclosure. In some examples, the base station 805 may be anexample of one or more aspects of the base stations 105, 205, or 205-aas described with reference to FIG. 1 or 2, or aspects of the apparatus605 as described with reference to FIG. 6. The base station 805 may beconfigured to implement or facilitate at least some of the base stationor apparatus techniques and functions as described with reference toFIG. 1, 2, 3, 4, or 6.

The base station 805 may include a base station processor 810, a basestation memory 820, at least one base station transceiver (representedby base station transceiver(s) 750), at least one base station antenna(represented by base station antenna(s) 855), or a base station wirelesscommunication manager 860. The base station 805 may also include one ormore of a network access device communicator 830 or a networkcommunicator 840. Each of these components may be in communication witheach other, directly or indirectly, over one or more buses 875.

The base station memory 820 may include RAM or ROM. The base stationmemory 820 may store computer-readable, computer-executable code 825containing instructions that are configured to, when executed, cause thebase station processor 810 to perform various functions described hereinrelated to wireless communication, including, for example, determining acontention window size for performing a LBT procedure with respect to ashared radio frequency spectrum band, transmitting an uplinktransmission over the shared radio frequency spectrum band, receivingaperiodic CSI for a carrier transmitted over the shared radio frequencyspectrum band, receiving a SRS over a carrier transmitted over theshared radio frequency spectrum band, etc. Alternatively, thecomputer-executable code 825 may not be directly executable by the basestation processor 810 but be configured to cause the base station 805(e.g., when compiled and executed) to perform various of the functionsdescribed herein.

The base station processor 810 may include an intelligent hardwaredevice, e.g., a CPU, a microcontroller, an ASIC, etc. The base stationprocessor 810 may process information received through the base stationtransceiver(s) 750, the network access device communicator 830, or thenetwork communicator 840. The base station processor 810 may alsoprocess information to be sent to the transceiver(s) 750 fortransmission through the antenna(s) 855, to the network access devicecommunicator 830, for transmission to one or more other network accessdevices (e.g., base station 805-a and/or base station 805-b), or to thenetwork communicator 840 for transmission to a core network 845, whichmay be an example of one or more aspects of the core network 130 asdescribed with reference to FIG. 1. The base station processor 810 mayhandle, alone or in connection with the base station wirelesscommunication manager 860, various aspects of communicating over (ormanaging communications over) a dedicated radio frequency spectrum bandor a shared radio frequency spectrum band.

The base station transceiver(s) 750 may include a modem configured tomodulate packets and provide the modulated packets to the base stationantenna(s) 855 for transmission, and to demodulate packets received fromthe base station antenna(s) 855. The base station transceiver(s) 750may, in some examples, be implemented as one or more base stationtransmitters and one or more separate base station receivers. The basestation transceiver(s) 750 may support communications in the dedicatedradio frequency spectrum band or the shared radio frequency spectrumband. The base station transceiver(s) 750 may be configured tocommunicate bi-directionally, via the base station antenna(s) 855, withone or more UEs or apparatuses, such as one or more of the UEs 115, 215,215-a, or 215-b as described with reference to FIG. 1 or 2, or one ormore of the apparatus 515 as described with reference to FIG. 5. Thebase station 805 may, for example, include multiple base stationantennas 855 (e.g., an antenna array). The base station 805 maycommunicate with the core network 845 through the network communicator840. The base station 805 may also communicate with other network accessdevices, such as the base station 805-a and/or the base station 805-b,using the network access device communicator 830.

The base station wireless communication manager 860 may be configured toperform or control some or all of the techniques or functions asdescribed with reference to FIG. 1, 2, 3, 4, or 6 related to wirelesscommunication over the dedicated radio frequency spectrum band or theshared radio frequency spectrum band. For example, the base stationwireless communication manager 860 may be configured to support asupplemental downlink mode (e.g., a licensed assisted access mode), acarrier aggregation mode (e.g., an enhanced licensed assisted accessmode), or a standalone mode using the dedicated radio frequency spectrumband or the shared radio frequency spectrum band. The base stationwireless communication manager 860 may include a base station LTE/LTE-Acomponent for dedicated RF spectrum band 865 configured to handleLTE/LTE-A communications in the dedicated radio frequency spectrum band,and a base station LTE/LTE-A component for shared RF spectrum band 870configured to handle LTE/LTE-A communications in the shared radiofrequency spectrum band. The base station wireless communication manager860, or portions of it, may include a processor, or some or all of thefunctions of the base station wireless communication manager 860 may beperformed by the base station processor 810 or in connection with thebase station processor 810. In some examples, the base station wirelesscommunication manager 860 may be an example of the wirelesscommunication manager 620 as described with reference to FIG. 6.

FIG. 9 is a flow chart illustrating an example of a method 900 forwireless communication at a network access device, in accordance withvarious aspects of the present disclosure. For clarity, the method 900is described below with reference to aspects of one or more of the basestations 105, 205, 205-a, or 805 as described with reference to FIG. 1,2, or 8, or aspects of the apparatus 605 as described with reference toFIG. 6. In some examples, a network access device may execute one ormore sets of codes to control the functional elements of the networkaccess device to perform the functions described below. Additionally oralternatively, the network access device may perform one or more of thefunctions described below using special-purpose hardware.

At block 905, the method 900 may include detecting a first referencesignal received from a UE in a reference scheduled transmission burstincluding a plurality of contiguous TTIs received over a shared radiofrequency spectrum band. The operation(s) at block 905 may be performedusing the wireless communication manager 620 as described with referenceto FIG. 6, the base station wireless communication manager 860 asdescribed with reference to FIG. 8, or the UE spectrum contentionmanager 640 as described with reference to FIG. 6.

At block 910, the method 900 may include identifying a reference TTI inwhich the first reference is received. The operation(s) at block 910 maybe performed using the wireless communication manager 620 as describedwith reference to FIG. 6, the base station wireless communicationmanager 860 as described with reference to FIG. 8, or the UE spectrumcontention manager 640 as described with reference to FIG. 6.

At block 915, the method 900 may include determining a contention windowsize usable by the UE to contend for access to the shared radiofrequency spectrum band. The determined contention window size may bebased at least in part on: a triggering of aperiodic CSI without a PUSCHon the reference TTI, a decoding of a PUCCH with CRC scheduled in thereference TTI, a decoding of a random access preamble scheduled on aPRACH in the reference TTI, a decoding of a first scheduled uplinktransmission associated with a random access procedure and received inthe reference TTI, or a combination thereof. The operation(s) at block915 may be performed using the wireless communication manager 620 asdescribed with reference to FIG. 6, the base station wirelesscommunication manager 860 as described with reference to FIG. 8, or theUE spectrum contention manager 640 as described with reference to FIG.6.

At block 920, the method 900 may include transmitting an indication ofthe determined contention window size to the UE. The operation(s) atblock 920 may be performed using the wireless communication manager 620as described with reference to FIG. 6, the base station wirelesscommunication manager 860 as described with reference to FIG. 8, or theUE spectrum contention manager 640 as described with reference to FIG.6.

FIG. 10 is a flow chart illustrating an example of a method 1000 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1000 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1005, the method 1000 may include receiving (e.g., from anetwork access device) at least one uplink grant of a plurality ofuplink grants for a reference scheduled transmission burst including aplurality of contiguous TTIs transmitted over a shared radio frequencyspectrum band. At least a first uplink grant in the plurality of uplinkgrants may include: a first indication that the first uplink grant isassociated with a first scheduled TTI of the reference scheduledtransmission burst, a second indication of a position of the firstscheduled TTI within the reference scheduled transmission burst, or acombination thereof. In some examples, each uplink grant for thereference scheduled transmission burst may include an indication of theposition of the first scheduled TTI of the reference scheduledtransmission burst. The operation(s) at block 1005 may be performedusing the wireless communication manager 520 as described with referenceto FIG. 5, the UE wireless communication manager 750 as described withreference to FIG. 7, or the uplink transmission manager 560 as describedwith reference to FIG. 5.

At block 1010, the method 1000 may include transmitting (e.g., to thenetwork access device) during at least one TTI of the referencescheduled transmission burst, in accordance with the at least one uplinkgrant. The transmitting may begin during a first transmission TTI. Theoperation(s) at block 1010 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the uplink transmission manager 560 as described with reference toFIG. 5.

At block 1015, the method 1000 may include receiving (e.g., from thenetwork access device) an indication of a reference TTI. The referenceTTI may be used for transmission by the UE during the referencescheduled transmission burst. In some examples, the indication of thereference TTI may be relative to the first scheduled TTI. Theoperation(s) at block 1015 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the uplink transmission manager 560 as described with reference toFIG. 5.

At block 1020, the method 1000 may include determining a contentionwindow size usable by the UE to contend for access to the shared radiofrequency spectrum band. The contention window size may be determinedbased at least in part on a relationship between the first scheduledTTI, the reference TTI, and the first transmission TTI. The operation(s)at block 1020 may be performed using the wireless communication manager520 as described with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the spectrumcontention manager 540 as described with reference to FIG. 5.

FIG. 11 is a flow chart illustrating an example of a method 1100 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1100 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1105, the method 1100 may include transmitting a referencescheduled transmission burst including a plurality of contiguous TTIsover a shared radio frequency spectrum band. The operation(s) at block1105 may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the uplinktransmission manager 560 as described with reference to FIG. 5.

At block 1110, the method 1100 may include identifying a HARQ processcorresponding to a reference TTI. The reference TTI may be a first TTIof the plurality of TTIs for which a HARQ acknowledgement is received.The operation(s) at block 1110 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the HARQ manager 565 as described with reference to FIG. 5.

At block 1115, the method 1100 may include identifying an instance ofthe HARQ process associated with a TTI subsequent to the reference TTI.The instance of the HARQ process may be identified based at least inpart on: whether the TTI is included within the reference scheduledtransmission burst or a subsequent transmission burst, whether the TTIincludes aperiodic CSI without a PUSCH, or a combination thereof. Theoperation(s) at block 1115 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the HARQ manager 565 as described with reference to FIG. 5.

At block 1120, the method 1100 may include determining a contentionwindow size usable by the UE to contend for access to the shared radiofrequency spectrum band. The contention window size may be determinedbased at least in part on a state of a NDI associated with theidentified instance of the HARQ process. The operation(s) at block 1120may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the spectrumcontention manager 540 as described with reference to FIG. 5.

FIG. 12 is a flow chart illustrating an example of a method 1200 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1200 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1205, the method 1200 may include receiving, in a CPDCCH, afirst indication of a RCOT for which a network access device has accessto a shared radio frequency spectrum band, and a second indication of apause time during which the network access device will not transmit overthe shared radio frequency spectrum band. In some examples, the RCOT mayinclude the pause time. In some examples, the RCOT may not include thepause time. The operation(s) at block 1205 may be performed using thewireless communication manager 520 as described with reference to FIG.5, the UE wireless communication manager 750 as described with referenceto FIG. 7, or the uplink transmission manager 560 as described withreference to FIG. 5.

At block 1210, the method 1200 may include determining, based at leastin part on the RCOT, whether a size of an uplink transmission of the UEallows the UE to transmit the uplink transmission within a MCOT forwhich the network access device has access to the shared radio frequencyspectrum band. The operation(s) at block 1210 may be performed using thewireless communication manager 520 as described with reference to FIG.5, the UE wireless communication manager 750 as described with referenceto FIG. 7, or the uplink transmission manager 560 as described withreference to FIG. 5.

At block 1215, the method 1200 may include entering a power saving modeduring at least a part of the pause time. The operation(s) at block 1215may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, or the UE wireless communicationmanager 750 as described with reference to FIG. 7.

FIG. 13 is a flow chart illustrating an example of a method 1300 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1300 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1305, the method 1300 may include receiving, in a downlink TTIof a scheduled transmission burst received over a shared radio frequencyspectrum band, an indication of a downlink-uplink TTI configurationbeginning with the downlink TTI. The downlink-uplink configuration mayinclude a number of upcoming downlink TTIs, a number of uplink TTIs, ora combination thereof. In some examples, the method 1300 may alsoinclude receiving, in the downlink TTI, at least one of: a secondindication of a downlink TTI duration, a third indication of an uplinkTTI duration, or a combination thereof. In some examples, the downlinkTTI may include a downlink subframe and the downlink-uplink TTIconfiguration may include a downlink-uplink subframe configuration. Theoperation(s) at block 1305 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the downlink transmission reception manager 535 as described withreference to FIG. 5.

At block 1310, the method 1300 may include determining, based at leastin part on the downlink-uplink TTI configuration beginning with thedownlink TTI, a timing of a next downlink TTI in the scheduledtransmission burst. The operation(s) at block 1310 may be performedusing the wireless communication manager 520 as described with referenceto FIG. 5, the UE wireless communication manager 750 as described withreference to FIG. 7, or the downlink transmission reception manager 535as described with reference to FIG. 5.

At block 1315, the method 1300 may optionally include receiving, in eachof at least one additional downlink TTI of the scheduled transmissionburst, an additional indication of an additional downlink-uplink TTIconfiguration following the additional downlink TTI. The operation(s) atblock 1315 may be performed using the wireless communication manager 520as described with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the downlinktransmission reception manager 535 as described with reference to FIG.5.

FIG. 14 is a flow chart illustrating an example of a method 1400 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1400 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1405, the method 1400 may include transmitting a type of B SR,which may include an indication of an amount of data to be transmittedfor each of a plurality of LBT priority classes. The operation(s) atblock 1405 may be performed using the wireless communication manager 520as described with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the BSR manager545 as described with reference to FIG. 5.

At block 1410, the method 1400 may include receiving from a networkaccess device, in response to transmitting the type of BSR, anindication of a LBT priority class boundary and an indication of a LBTpriority class to be used by the UE when contending for access to ashared radio frequency spectrum band. The operation(s) at block 1410 maybe performed using the wireless communication manager 520 as describedwith reference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the spectrum contention manager540 as described with reference to FIG. 5.

At block 1415, the method 1400 may include selecting a LBT priorityclass based at least in part on a type of data to be transmitted over ashared radio frequency spectrum band and the LBT priority classboundary. In some examples, the LBT priority class boundary may includeat least one of: a highest LBT priority class usable by the UE, a lowestLBT priority class usable by the UE, or a combination thereof. Theoperation(s) at block 1415 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the spectrum contention manager 540 as described with reference toFIG. 5.

At block 1420, the method 1400 may include contending for access to theshared radio frequency spectrum band based at least in part on theselected LBT priority class. The operation(s) at block 1420 may beperformed using the wireless communication manager 520 as described withreference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the spectrum contention manager540 as described with reference to FIG. 5.

FIG. 15 is a flow chart illustrating an example of a method 1500 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1500 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1505, the method 1500 may include transmitting a first type ofBSR including an indication of an amount of data to be transmitted foreach of a plurality of LBT priority classes. The operation(s) at block1505 may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the BSR manager545 as described with reference to FIG. 5.

At block 1510, the method 1500 may include receiving from a networkaccess device, in response to transmitting the first type of BSR, anindication of a LBT priority class to be used by the UE when contendingfor access to a shared radio frequency spectrum band. The operation(s)at block 1510 may be performed using the wireless communication manager520 as described with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the spectrumcontention manager 540 as described with reference to FIG. 5.

In some examples, the method 1500 may include selecting the first typeof BSR from a plurality of BSR types including at least the first typeof BSR and a second type of BSR. In some examples, the second type ofBSR may include a LTE/LTE-A type of BSR. In some examples, the firsttype of BSR may be selected from the plurality of BSR types based atleast in part on a BSR selection criterion. In some examples, thecriterion may include receiving data to transmit, in which the data isassociated with a LBT priority class satisfying (e.g., exceeding) athreshold LBT priority class.

FIG. 16 is a flow chart illustrating an example of a method 1600 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1600 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1605, the method 1600 may include receiving a first uplinkgrant for transmitting over a shared radio frequency spectrum band. Thefirst uplink grant may be associated with a first LBT priority class.The operation(s) at block 1605 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the uplink transmission manager 560 as described with reference toFIG. 5.

At block 1610, the method 1600 may include performing a first LBTprocedure based at least in part on the first LBT priority class tocontend for access to the shared radio frequency spectrum band. Thefirst LBT procedure may conclude at a LBT state. The operation(s) atblock 1610 may be performed using the wireless communication manager 520as described with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the spectrumcontention manager 540 as described with reference to FIG. 5.

At block 1615, the method 1600 may include determining, based at leastin part on the LBT state, to not transmit over the shared radiofrequency spectrum band in accordance with the first uplink grant. Theoperation(s) at block 1615 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the spectrum contention manager 540 as described with reference toFIG. 5.

At block 1620, the method 1600 may include receiving a second uplinkgrant for transmitting over the shared radio frequency spectrum band.The second uplink grant may be associated with a second LBT priorityclass. The operation(s) at block 1620 may be performed using thewireless communication manager 520 as described with reference to FIG.5, the UE wireless communication manager 750 as described with referenceto FIG. 7, or the uplink transmission manager 560 as described withreference to FIG. 5.

At block 1625, the method 1600 may optionally include adjusting the LBTstate based at least in part on a difference between the first LBTpriority class and the second LBT priority class. Accordingly, in somecases, the LBT state may be adjusted at the conclusion of the first LBTprocedure. Additionally or alternatively, the second LBT procedure maybe initialized. In some examples, the operation(s) at block 1625 mayinclude determining the first LBT priority class and the second LBTpriority class are a same LBT priority class, and initializing thesecond LBT procedure based at least in part on the LBT state. In someexamples, the operation(s) at block 1625 may include determining thefirst LBT priority class and the second LBT priority class are differentLBT priority classes, adjusting the LBT state at the conclusion of thefirst LBT procedure based at least in part on a difference between thefirst LBT priority class and the second LBT priority class, andinitializing the second LBT procedure based at least in part on theadjusted LBT state. The operation(s) at block 1625 may be performedusing the wireless communication manager 520 as described with referenceto FIG. 5, the UE wireless communication manager 750 as described withreference to FIG. 7, or the spectrum contention manager 540 as describedwith reference to FIG. 5.

At block 1630, the method 1600 may include performing a second LBTprocedure based at least in part on the second LBT priority class, thefirst LBT priority class, and the LBT state to contend for access to theshared radio frequency spectrum band. The operation(s) at block 1630 maybe performed using the wireless communication manager 520 as describedwith reference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the spectrum contention manager540 as described with reference to FIG. 5.

FIG. 17 is a flow chart illustrating an example of a method 1700 forwireless communication at a network access device, in accordance withvarious aspects of the present disclosure. For clarity, the method 1700is described below with reference to aspects of one or more of the basestations 105, 205, 205-a, or 805 as described with reference to FIG. 1,2, or 8, or aspects of the apparatus 605 as described with reference toFIG. 6. In some examples, a network access device may execute one ormore sets of codes to control the functional elements of the networkaccess device to perform the functions described below. Additionally oralternatively, the network access device may perform one or more of thefunctions described below using special-purpose hardware.

At block 1705, the method 1700 may include identifying feedback receivedfrom a UE for a downlink reference TTI of a TxOP over a shared radiofrequency spectrum band. The TxOP may include at least one downlink TTIand at least one uplink TTI. In some examples, the at least one downlinkTTI may include at least one downlink subframe, and the at least oneuplink TTI may include at least one uplink subframe. The operation(s) atblock 1705 may be performed using the wireless communication manager 620as described with reference to FIG. 6, the base station wirelesscommunication manager 860 as described with reference to FIG. 8, or theHARQ manager 645 as described with reference to FIG. 6.

At block 1710, the method 1700 may include identifying an uplink TTI, ofthe TxOP, for which scheduling information is transmitted in thedownlink reference TTI. The operation(s) at block 1710 may be performedusing the wireless communication manager 620 as described with referenceto FIG. 6, the base station wireless communication manager 860 asdescribed with reference to FIG. 8, or the network access devicespectrum contention manager 635 as described with reference to FIG. 6.

At block 1715, the method 1700 may include determining a contentionwindow size usable by the network access device to contend for access tothe shared radio frequency spectrum band, for a next TxOP, based atleast in part on the identified feedback and a scheduled uplinktransmission in the identified uplink TTI. In some examples, determiningthe contention window size based at least in part on the scheduleduplink transmission in the identified uplink TTI may include determiningthe contention window size based at least in part on a decoding of atleast one channel including: a scheduled PUSCH, or a scheduled PUCCH, ora scheduled PRACH, or a combination thereof. In some examples,determining the contention window size based at least in part on thedecoding of the at least one channel may include determining thecontention window size based least in part on ACK/NACK feedback for theat least one channel. The operation(s) at block 1715 may be performedusing the wireless communication manager 620 as described with referenceto FIG. 6, the base station wireless communication manager 860 asdescribed with reference to FIG. 8, or the network access devicespectrum contention manager 635 as described with reference to FIG. 6.

FIG. 18 is a flow chart illustrating an example of a method 1800 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1800 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 1805, the method 1800 may include receiving schedulinginformation for an uplink transmission to be made over a plurality ofcarriers of a shared radio frequency spectrum band. The operation(s) atblock 1805 may be performed using the wireless communication manager 520as described with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the uplinktransmission manager 560 as described with reference to FIG. 5.

At block 1810, the method 1800 may include identifying a carrier of theplurality of carriers for which to perform a first type of LBTprocedure. In some examples, identifying the carrier may include one of:identifying the carrier from an indication received from a networkaccess device, or independently identifying the carrier. Theoperation(s) at block 1810 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the spectrum contention manager 540 as described with reference toFIG. 5.

At block 1815, the method 1800 may include performing the first type ofLBT procedure for the identified carrier. The operation(s) at block 1815may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the spectrumcontention manager 540 as described with reference to FIG. 5.

At block 1820, the method 1800 may include performing a second type ofLBT procedure for each carrier of the plurality of carriers other thanthe identified carrier. The second type of LBT procedure may have ashorter contention window than the first type of LBT procedure. Theoperation(s) at block 1820 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the spectrum contention manager 540 as described with reference toFIG. 5.

At block 1825, the method 1800 may include transmitting the uplinktransmission over the plurality of carriers based at least in part onthe performance of the first type of LBT procedure for the identifiedcarrier and the performance of the second type of LBT procedure for eachcarrier other than the identified carrier. The operation(s) at block1825 may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the uplinktransmission manager 560 as described with reference to FIG. 5.

FIG. 19 is a flow chart illustrating an example of a method 1900 forwireless communication at a network access device, in accordance withvarious aspects of the present disclosure. For clarity, the method 1900is described below with reference to aspects of one or more of the basestations 105, 205, 205-a, or 805 as described with reference to FIG. 1,2, or 8, or aspects of the apparatus 605 as described with reference toFIG. 6. In some examples, a network access device may execute one ormore sets of codes to control the functional elements of the networkaccess device to perform the functions described below. Additionally oralternatively, the network access device may perform one or more of thefunctions described below using special-purpose hardware.

At block 1905, the method 1900 may include scheduling an uplinktransmission to be made by a UE over a plurality of carriers of a sharedradio frequency spectrum band. The operation(s) at block 1905 may beperformed using the wireless communication manager 620 as described withreference to FIG. 6, the base station wireless communication manager 860as described with reference to FIG. 8, or the uplink transmissionmanager 660 as described with reference to FIG. 6.

At block 1910, the method 1900 may include transmitting, to the UE, anindication of a single carrier of the plurality of carriers for which toperform a first type of LBT procedure. In some examples, transmittingthe indication of the single carrier may include: transmitting theindication of the single carrier in uplink DCI for the single carrier,or transmitting the indication of the single carrier in uplink DCI foreach carrier of the plurality of carriers. The operation(s) at block1910 may be performed using the wireless communication manager 620 asdescribed with reference to FIG. 6, the base station wirelesscommunication manager 860 as described with reference to FIG. 8, or theUE spectrum contention manager 640 as described with reference to FIG.6.

FIG. 20 is a flow chart illustrating an example of a method 2000 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 2000 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 2005, the method 2000 may include identifying a type of LBTprocedure to be performed for contending for access to a shared radiofrequency spectrum band. The identified type of LBT procedure mayinclude a first type of LBT procedure or a second type of LBT procedure.The operation(s) at block 2005 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the spectrum contention manager 540 as described with reference toFIG. 5.

At block 2010, the method 2000 may include identifying an energydetection threshold associated with the identified type of LBTprocedure, the identified energy detection threshold including a firstenergy detection threshold for the first type of LBT procedure or asecond energy detection threshold for the second type of LBT procedure,where the first energy detection threshold may be lower than the secondenergy detection threshold. The operation(s) at block 2010 may beperformed using the wireless communication manager 520 as described withreference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the spectrum contention manager540 as described with reference to FIG. 5.

At block 2015, the method 2000 may include performing the identifiedtype of LBT procedure based at least in part on the identified energydetection threshold to contend for access to the shared radio frequencyspectrum band. The operation(s) at block 2015 may be performed using thewireless communication manager 520 as described with reference to FIG.5, the UE wireless communication manager 750 as described with referenceto FIG. 7, or the spectrum contention manager 540 as described withreference to FIG. 5.

FIG. 21 is a flow chart illustrating an example of a method 2100 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 2100 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 2105, the method 2100 may include receiving an indication thatthe UE cannot update a countdown counter associated with performance ofa LBT procedure during a TTI in which the UE receives a transmission. Insome examples, the indication that the UE cannot update the countdowncounter may be received in at least one of: RRC signaling, a SIB, orDCI. The operation(s) at block 2105 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the spectrum contention manager 540 as described with reference toFIG. 5.

At block 2110, the method 2100 may include determining the UE isreceiving a transmission during a TTI. The operation(s) at block 2110may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the downlinktransmission reception manager 535 as described with reference to FIG.5.

At block 2115, the method 2100 may include refraining from at least oneof: performing a LBT procedure during the TTI, updating a countdowncounter associated with performance of the LBT procedure during the TTI,or a combination thereof. The operation(s) at block 2115 may beperformed using the wireless communication manager 520 as described withreference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the spectrum contention manager540 as described with reference to FIG. 5.

FIG. 22 is a flow chart illustrating an example of a method 2200 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 2200 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 2205, the method 2200 may include receiving an indication of atransmission parameter for an uplink transmission to be made over ashared radio frequency spectrum band during at least one TTI. In someexamples, the transmission parameter may include at least one of: a TBS,a MCS, or a combination thereof. The operation(s) at block 2205 may beperformed using the wireless communication manager 520 as described withreference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the uplink transmission manager560 as described with reference to FIG. 5.

At block 2210, the method 2200 may include identifying a content of theuplink transmission in each TTI of the at least one TTI. In someexamples, the identified content may include at least one of: a numberof REs, a number of punctured symbol periods, a first presence of aPUCCH, a second presence of a PRACH, a third presence of a SRS, or acombination thereof. The operation(s) at block 2210 may be performedusing the wireless communication manager 520 as described with referenceto FIG. 5, the UE wireless communication manager 750 as described withreference to FIG. 7, or the uplink transmission manager 560 as describedwith reference to FIG. 5.

At block 2215, the method 2200 may include scaling the transmissionparameter for at least a first TTI based on an identified content of theuplink transmission in the first TTI. In some examples, scaling thetransmission parameter may include one of: switching to a fixedalternative transmission parameter, or computing an alternativetransmission parameter based at least in part on a comparison of theidentified content to a nominal content. The operation(s) at block 2215may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the uplinktransmission manager 560 as described with reference to FIG. 5.

FIG. 23 is a flow chart illustrating an example of a method 2300 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 2300 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 2305, the method 2300 may include receiving RRC signaling froma network. The RRC signaling may configure HARQ ACK feedback reportingfor a first carrier in a shared radio frequency spectrum band in one of:a first mode in which the UE transmits HARQ ACK feedback is transmittedon a PUCCH on a second carrier in a dedicated radio frequency spectrumband, or a second mode in which the UE selects to transmit HARQ ACKfeedback on the PUCCH on the second carrier or on a PUSCH on the firstcarrier. The operation(s) at block 2305 may be performed using thewireless communication manager 520 as described with reference to FIG.5, the UE wireless communication manager 750 as described with referenceto FIG. 7, or the HARQ manager 565 as described with reference to FIG.5.

At block 2310, the method 2300 may include transmitting HARQ ACKfeedback in accordance with the first mode or the second mode, asconfigured by the RRC signaling. The operation(s) at block 2310 may beperformed using the wireless communication manager 520 as described withreference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the HARQ manager 565 as describedwith reference to FIG. 5.

In some examples of the method 2300, the RRC signaling may configure theHARQ ACK feedback reporting for the first carrier in the second mode,and the method 2300 may include contending for access to the firstcarrier in the shared radio frequency spectrum band, and selecting totransmit HARQ ACK feedback on the PUSCH on the first carrier based atleast in part on winning contention for access to the first carrier.

FIG. 24 is a flow chart illustrating an example of a method 2400 forwireless communication at a network access device, in accordance withvarious aspects of the present disclosure. For clarity, the method 2400is described below with reference to aspects of one or more of the basestations 105, 205, 205-a, or 805 as described with reference to FIG. 1,2, or 8, or aspects of the apparatus 605 as described with reference toFIG. 6. In some examples, a network access device may execute one ormore sets of codes to control the functional elements of the networkaccess device to perform the functions described below. Additionally oralternatively, the network access device may perform one or more of thefunctions described below using special-purpose hardware.

At block 2405, the method 2400 may include configuring HARQ ACK feedbackreporting for a first carrier in a shared radio frequency spectrum inone of: a first mode in which a UE transmits HARQ ACK feedback on aPUCCH on a second carrier in a dedicated radio frequency spectrum band,or a second mode in which the UE selects to transmit HARQ ACK feedbackon the PUCCH on the second carrier or on a PUSCH on the first carrier.The operation(s) at block 2405 may be performed using the wirelesscommunication manager 620 as described with reference to FIG. 6, thebase station wireless communication manager 860 as described withreference to FIG. 8, or the HARQ manager 645 as described with referenceto FIG. 6.

At block 2410, the method 2400 may include transmitting an indication ofthe configured HARQ ACK feedback reporting mode to the UE in RRCsignaling. The operation(s) at block 2410 may be performed using thewireless communication manager 620 as described with reference to FIG.6, the base station wireless communication manager 860 as described withreference to FIG. 8, or the HARQ manager 645 as described with referenceto FIG. 6.

At block 2415, the method 2400 may include receiving HARQ ACK feedbackfor the first carrier from the UE, in accordance with the configuredHARQ ACK feedback reporting mode. The operation(s) at block 2415 may beperformed using the wireless communication manager 620 as described withreference to FIG. 6, the base station wireless communication manager 860as described with reference to FIG. 8, or the HARQ manager 645 asdescribed with reference to FIG. 6.

FIG. 25 is a flow chart illustrating an example of a method 2500 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 2500 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 2505, the method 2500 may include receiving an indication of aninvalid PUSCH resource allocation for a TTI over a shared radiofrequency spectrum band. In some examples, the invalid PUSCH resourceallocation may include an invalid frequency interlace combination with adesignated bit pattern for a RV and a NDI. The operation(s) at block2505 may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the CSI manager555 as described with reference to FIG. 5.

At block 2510, the method 2500 may include transmitting aperiodic CSIwithout a PUSCH in the TTI. The operation(s) at block 2510 may beperformed using the wireless communication manager 520 as described withreference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the CSI manager 555 as describedwith reference to FIG. 5.

At block 2515, the method 2500 may optionally include interpreting aHARQ ID for the TTI as invalid. The operation(s) at block 2515 may beperformed using the wireless communication manager 520 as described withreference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the HARQ manager 565 as describedwith reference to FIG. 5.

FIG. 26 is a flow chart illustrating an example of a method 2600 forwireless communication at a network access device, in accordance withvarious aspects of the present disclosure. For clarity, the method 2600is described below with reference to aspects of one or more of the basestations 105, 205, 205-a, or 805 as described with reference to FIG. 1,2, or 8, or aspects of the apparatus 605 as described with reference toFIG. 6. In some examples, a network access device may execute one ormore sets of codes to control the functional elements of the networkaccess device to perform the functions described below. Additionally oralternatively, the network access device may perform one or more of thefunctions described below using special-purpose hardware.

At block 2605, the method 2600 may include transmitting an indication ofan invalid PUSCH resource allocation for a TTI over a shared radiofrequency spectrum band. In some examples, the invalid PUSCH resourceallocation comprises an invalid frequency interlace combination with adesignated bit pattern for a RV and a NDI. The operation(s) at block2605 may be performed using the wireless communication manager 620 asdescribed with reference to FIG. 6, the base station wirelesscommunication manager 860 as described with reference to FIG. 8, or theuplink transmission manager 660 as described with reference to FIG. 6.

At block 2610, the method 2600 may include receiving aperiodic CSIwithout a PUSCH in the TTI. The operation(s) at block 2610 may beperformed using the wireless communication manager 620 as described withreference to FIG. 6, the base station wireless communication manager 860as described with reference to FIG. 8, or the CSI manager 655 asdescribed with reference to FIG. 6.

FIG. 27 is a flow chart illustrating an example of a method 2700 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 2700 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 2705, the method 2700 may include receiving a code pointassociated with transmission of aperiodic CSI over a shared radiofrequency spectrum band in a TTI scheduled without a PUSCH. Theoperation(s) at block 2705 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the CSI manager 555 as described with reference to FIG. 5.

At block 2710, the method 2700 may include receiving a multi-TTI grantthat references the code point for a TTI scheduled by the multi-TTIgrant. The operation(s) at block 2705 may be performed using thewireless communication manager 520 as described with reference to FIG.5, the UE wireless communication manager 750 as described with referenceto FIG. 7, or the uplink transmission manager 560 as described withreference to FIG. 5.

At block 2715, the method 2700 may include transmitting aperiodic CSIwithout a PUSCH in the TTI, in accordance with the code point. Theoperation(s) at block 2705 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the CSI manager 555 as described with reference to FIG. 5.

FIG. 28 is a flow chart illustrating an example of a method 2800 forwireless communication at a network access device, in accordance withvarious aspects of the present disclosure. For clarity, the method 2800is described below with reference to aspects of one or more of the basestations 105, 205, 205-a, or 805 as described with reference to FIG. 1,2, or 8, or aspects of the apparatus 605 as described with reference toFIG. 6. In some examples, a network access device may execute one ormore sets of codes to control the functional elements of the networkaccess device to perform the functions described below. Additionally oralternatively, the network access device may perform one or more of thefunctions described below using special-purpose hardware.

At block 2805, the method 2800 may include identifying an expectedfrequency of SRS requests. The operation(s) at block 2805 may beperformed using the wireless communication manager 620 as described withreference to FIG. 6, the base station wireless communication manager 860as described with reference to FIG. 8, or the SRS manager 650 asdescribed with reference to FIG. 6.

At block 2810, the method 2800 may include identifying an aperiodic SRSto be transmitted without a PUSCH, during a TTI, over a shared radiofrequency spectrum band. The operation(s) at block 2810 may be performedusing the wireless communication manager 620 as described with referenceto FIG. 6, the base station wireless communication manager 860 asdescribed with reference to FIG. 8, or the SRS manager 650 as describedwith reference to FIG. 6.

At block 2815, the method 2800 may include determining a contentionwindow size to be used by a UE when performing a LBT procedure tocontend for access to the shared radio frequency spectrum band totransmit the aperiodic SRS, the determined contention window size basedat least in part on the expected frequency of SRS requests. Theoperation(s) at block 2815 may be performed using the wirelesscommunication manager 620 as described with reference to FIG. 6, thebase station wireless communication manager 860 as described withreference to FIG. 8, or the UE spectrum contention manager 640 asdescribed with reference to FIG. 6.

At block 2820, the method 2800 may include transmitting an indication ofthe determined contention window size to the UE. In some examples, theindication of the determined contention window size may be transmittedin RRC signaling. The operation(s) at block 2820 may be performed usingthe wireless communication manager 620 as described with reference toFIG. 6, the base station wireless communication manager 860 as describedwith reference to FIG. 8, or the UE spectrum contention manager 640 asdescribed with reference to FIG. 6.

FIG. 29 is a flow chart illustrating an example of a method 2900 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 2900 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 2905, the method 2900 may include receiving, in downlink DCI, atrigger to transmit a SRS during a TTI. The operation(s) at block 2905may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the SRS manager550 as described with reference to FIG. 5.

At block 2910, the method 2900 may include receiving schedulinginformation for a PUSCH to be transmitted during the TTI, in which thescheduling information does not include a gap for transmitting the SRS.The operation(s) at block 2910 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the uplink transmission manager 560 as described with reference toFIG. 5.

At block 2915, the method 2900 may include transmitting, during the TTI,one of: the PUSCH rate matched around the SRS, the PUSCH punctured bythe SRS, the PUSCH without the SRS, or the SRS without the PUSCH. Theoperation(s) at block 2915 may be performed using the wirelesscommunication manager 520 as described with reference to FIG. 5, the UEwireless communication manager 750 as described with reference to FIG.7, or the uplink transmission manager 560 or SRS manager 550 asdescribed with reference to FIG. 5.

FIG. 30 is a flow chart illustrating an example of a method 3000 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 3000 is described belowwith reference to aspects of one or more of the UEs 115, 215, 215-a,215-b, or 715 as described with reference to FIG. 1, 2, or 7, or aspectsof the apparatus 515 as described with reference to FIG. 5. In someexamples, a UE may execute one or more sets of codes to control thefunctional elements of the UE to perform the functions described below.Additionally or alternatively, the UE may perform one or more of thefunctions described below using special-purpose hardware.

At block 3005, the method 3000 may include receiving a first indicationof a default initial timing advance for a first carrier in a sharedradio frequency spectrum band. The default initial timing advance mayinclude: a timing advance of a second carrier in a dedicated radiofrequency spectrum band, wherein the first carrier and the secondcarrier are in a same TAG, or a static initial timing advance (e.g., aTA of “0”), or a combination thereof. The operation(s) at block 3005 maybe performed using the wireless communication manager 520 as describedwith reference to FIG. 5, the UE wireless communication manager 750 asdescribed with reference to FIG. 7, or the uplink transmission manager560 as described with reference to FIG. 5.

At block 3010, the method 3000 may include receiving a second indicationof a default initial uplink transmit power. In some examples, thedefault initial uplink transmit power may be a maximum uplink transmitpower. In some examples, the second indication may be received in atleast one of: a system information block, a RRC configuration, or acombination thereof. In some examples, the method 3000 may includereceiving a plurality of code points indicating different uplinktransmit power adjustment steps, and a code point providing the secondindication. The operation(s) at block 3010 may be performed using thewireless communication manager 520 as described with reference to FIG.5, the UE wireless communication manager 750 as described with referenceto FIG. 7, or the uplink transmission manager 560 as described withreference to FIG. 5.

At block 3015, the method 3000 may include transmitting on the firstcarrier based at least in part on the default initial timing advance andthe default initial uplink transmit power. The operation(s) at block3015 may be performed using the wireless communication manager 520 asdescribed with reference to FIG. 5, the UE wireless communicationmanager 750 as described with reference to FIG. 7, or the uplinktransmission manager 560 as described with reference to FIG. 5.

FIG. 31 is a flow chart illustrating an example of a method 3100 forwireless communication at a network access device, in accordance withvarious aspects of the present disclosure. For clarity, the method 3100is described below with reference to aspects of one or more of the basestations 105, 205, 205-a, or 805 as described with reference to FIG. 1,2, or 8, or aspects of the apparatus 605 as described with reference toFIG. 6. In some examples, a network access device may execute one ormore sets of codes to control the functional elements of the networkaccess device to perform the functions described below. Additionally oralternatively, the network access device may perform one or more of thefunctions described below using special-purpose hardware.

At block 3105, the method 3100 may include selecting, from a pluralityof code points, at least one of: a first code point for controllingtransmit power in a single TTI uplink transmission, a second code pointfor controlling transmit power in a multi-TTI uplink transmission, athird code point associated with transmitting at a maximum transmitpower during a single TTI uplink transmission or a multi-TTI uplinktransmission, or a combination thereof. The first code point and thesecond code point may be associated with different transmit powers(e.g., different ranges of transmit powers). In some examples of themethod 3100, the second code point may identify larger uplink transmitpower adjustment steps than the first code point. The operation(s) atblock 3105 may be performed using the wireless communication manager 620as described with reference to FIG. 6, the base station wirelesscommunication manager 860 as described with reference to FIG. 8, or theuplink transmission manager 660 as described with reference to FIG. 6.

At block 3110, the method 3100 may include transmitting a transmit powercontrol (TPC) command to a UE. The TPC command may include the at leastone code point selected at block 3105. The operation(s) at block 3110may be performed using the wireless communication manager 620 asdescribed with reference to FIG. 6, the base station wirelesscommunication manager 860 as described with reference to FIG. 8, or theuplink transmission manager 660 as described with reference to FIG. 6.

In some examples, the method 3100 may further include scheduling anuplink transmission by the UE, in which the scheduled uplinktransmission includes a single TTI uplink transmission or a multi-TTIuplink transmission. The method 3100 may also include transmitting, tothe UE, an uplink grant referencing a code point transmitted in the TPCcommand.

The methods 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800,1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700, 2800, 2900, 3000,and 3100 as described with reference to FIGS. 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, and 31illustrate just some techniques, and some implementations of techniques,described in the present disclosure. In some examples, aspects from twoor more of the methods 900, 1700, 1900, 2400, 2600, 2800, or 3100described with reference to FIGS. 9, 17, 19, 24, 26, 28, and 31 may becombined. In some examples, aspects of the methods 1000, 1100, 1200,1300, 1400, 1500, 1600, 1800, 2000, 2100, 2200, 2300, 2500, 2700, 2900,or 3000 as described with reference to FIGS. 10, 11, 12, 13, 14, 15, 16,18, 20, 21, 22, 23, 25, 27, and 29 may be combined. It should be notedthat the methods are just example implementations, and that theoperations of the methods may be rearranged or otherwise modified suchthat other implementations are possible.

Techniques described herein may be used for various wirelesscommunication systems such as code-division multiple access (CDMA),time-division multiple access (TDMA), FDMA, OFDMA, SC-FDMA, and othersystems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asCDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and Amay be referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) may bereferred to as CDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRAincludes Wideband CDMA (WCDMA) and other variants of CDMA. A TDMA systemmay implement a radio technology such as Global System for MobileCommunications (GSM). An OFDMA system may implement a radio technologysuch as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11(Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM™, etc. UTRA andE-UTRA are part of Universal Mobile Telecommunication System (UMTS).3GPP LTE and LTE-A are new releases of UMTS that use E-UTRA. UTRA,E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from anorganization named 3GPP. CDMA2000 and UMB are described in documentsfrom an organization named “3rd Generation Partnership Project 2”(3GPP2). The techniques described herein may be used for the systems andradio technologies mentioned above as well as other systems and radiotechnologies, including cellular (e.g., LTE) communications over ashared radio frequency spectrum band. The description above, however,describes an LTE/LTE-A system for purposes of example, and LTEterminology is used in much of the description above, although thetechniques are applicable beyond LTE/LTE-A applications.

The detailed description set forth above in connection with the appendeddrawings describes examples and does not represent all of the examplesthat may be implemented or that are within the scope of the claims. Theterms “example” and “exemplary,” when used in this description, mean“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other examples.” The detailed description includesspecific details for the purpose of providing an understanding of thedescribed techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand apparatuses are shown in block diagram form in order to avoidobscuring the concepts of the described examples.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connectionwith the disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), an ASIC, afield-programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general-purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration.

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Features implementingfunctions may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. As used herein, including in the claims,the term “and/or,” when used in a list of two or more items, means thatany one of the listed items can be employed by itself, or anycombination of two or more of the listed items can be employed. Forexample, if a composition is described as containing components A, B,and/or C, the composition can contain A alone; B alone; C alone; A and Bin combination; A and C in combination; B and C in combination; or A, B,and C in combination. Also, as used herein, including in the claims,“or” as used in a list of items (for example, a list of items prefacedby a phrase such as “at least one of” or “one or more of”) indicates aninclusive list such that, for example, a phrase referring to “at leastone of” a list of items refers to any combination of those items,including single members. As an example, “at least one of: A, B, or C”is intended to cover A, B, C, A-B, A-C, B-C, and A-B-C., as well as anycombination with multiples of the same element (e.g., A-A, A-A-A, A-A-B,A-A-C, A-B-B, A-C-C, B-B, B-B-B, B-B-C, C-C, and C-C-C or any otherordering of A, B, and C).

As used herein, the phrase “based on” shall not be construed as areference to a closed set of conditions. For example, an exemplary stepthat is described as “based on condition A” may be based on both acondition A and a condition B without departing from the scope of thepresent disclosure. In other words, as used herein, the phrase “basedon” shall be construed in the same manner as the phrase “based at leastin part on.”

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media cancomprise RAM, ROM, electrically erasable programmable read only memory(EEPROM), compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the scope of thedisclosure. Thus, the disclosure is not to be limited to the examplesand designs described herein but is to be accorded the broadest scopeconsistent with the principles and novel techniques disclosed herein.

What is claimed is:
 1. A method for wireless communication at a userequipment (UE), comprising: receiving a first uplink grant fortransmitting over a shared radio frequency spectrum band, the firstuplink grant associated with a first listen before talk (LBT) priorityclass; performing a first LBT procedure based at least in part on thefirst LBT priority class to contend for access to the shared radiofrequency spectrum band, the first LBT procedure concluding at a LBTstate; determining, based at least in part on the LBT state, to nottransmit over the shared radio frequency spectrum band in accordancewith the first uplink grant; receiving a second uplink grant fortransmitting over the shared radio frequency spectrum band, the seconduplink grant associated with a second LBT priority class; and performinga second LBT procedure based at least in part on the second LBT priorityclass, the first LBT priority class, and the LBT state to contend foraccess to the shared radio frequency spectrum band.
 2. The method ofclaim 1, further comprising: determining the first LBT priority classand the second LBT priority class are a same LBT priority class; andinitializing the second LBT procedure based at least in part on the LBTstate.
 3. The method of claim 1, further comprising: determining thefirst LBT priority class and the second LBT priority class are differentLBT priority classes; adjusting the LBT state based at least in part ona difference between the first LBT priority class and the second LBTpriority class; and initializing the second LBT procedure based at leastin part on the adjusted LBT state.
 4. An apparatus for wirelesscommunication at a user equipment (UE), comprising: a processor, memoryin electronic communication with the processor; and instructions storedin the memory and executable by the processor to cause the apparatus to:receive a first uplink grant for transmitting over a shared radiofrequency spectrum band, the first uplink grant associated with a firstlisten before talk (LBT) priority class; perform a first LBT procedurebased at least in part on the first LBT priority class to contend foraccess to the shared radio frequency spectrum band, the first LBTprocedure concluding at a LBT state; determine, based at least in parton the LBT state, to not transmit over the shared radio frequencyspectrum band in accordance with the first uplink grant; receive asecond uplink grant for transmitting over the shared radio frequencyspectrum band, the second uplink grant associated with a second LBTpriority class; and perform a second LBT procedure based at least inpart on the second LBT priority class, the first LBT priority class, andthe LBT state to contend for access to the shared radio frequencyspectrum band.
 5. The apparatus of claim 4, wherein the instructions arefurther executable by the processor to cause the apparatus to: determinethe first LBT priority class and the second LBT priority class are asame LBT priority class; and initialize the second LBT procedure basedat least in part on the LBT state.
 6. The apparatus of claim 4, whereinthe instructions are further executable by the processor to cause theapparatus to: determine the first LBT priority class and the second LBTpriority class are different LBT priority classes; adjust the LBT statebased at least in part on a difference between the first LBT priorityclass and the second LBT priority class; and initialize the second LBTprocedure based at least in part on the adjusted LBT state.
 7. Anapparatus for wireless communication at a user equipment (UE),comprising: means for receiving a first uplink grant for transmittingover a shared radio frequency spectrum band, the first uplink grantassociated with a first listen before talk (LBT) priority class; meansfor performing a first LBT procedure based at least in part on the firstLBT priority class to contend for access to the shared radio frequencyspectrum band, the first LBT procedure concluding at a LBT state; meansfor determining, based at least in part on the LBT state, to nottransmit over the shared radio frequency spectrum band in accordancewith the first uplink grant; means for receiving a second uplink grantfor transmitting over the shared radio frequency spectrum band, thesecond uplink grant associated with a second LBT priority class; andmeans for performing a second LBT procedure based at least in part onthe second LBT priority class, the first LBT priority class, and the LBTstate to contend for access to the shared radio frequency spectrum band.8. The apparatus of claim 7, further comprising: means for determiningthe first LBT priority class and the second LBT priority class are asame LBT priority class; and means for initializing the second LBTprocedure based at least in part on the LBT state.
 9. The apparatus ofclaim 7, further comprising: means for determining the first LBTpriority class and the second LBT priority class are different LBTpriority classes; means for adjusting the LBT state based at least inpart on a difference between the first LBT priority class and the secondLBT priority class; and means for initializing the second LBT procedurebased at least in part on the adjusted LBT state.
 10. A non-transitorycomputer-readable medium storing code for wireless communication at auser equipment (UE), the code comprising instructions executable by aprocessor to: receive a first uplink grant for transmitting over ashared radio frequency spectrum band, the first uplink grant associatedwith a first listen before talk (LBT) priority class; perform a firstLBT procedure based at least in part on the first LBT priority class tocontend for access to the shared radio frequency spectrum band, thefirst LBT procedure concluding at a LBT state; determine, based at leastin part on the LBT state, to not transmit over the shared radiofrequency spectrum band in accordance with the first uplink grant;receive a second uplink grant for transmitting over the shared radiofrequency spectrum band, the second uplink grant associated with asecond LBT priority class; and perform a second LBT procedure based atleast in part on the second LBT priority class, the first LBT priorityclass, and the LBT state to contend for access to the shared radiofrequency spectrum band.
 11. The non-transitory computer-readable mediumof claim 10, wherein the instructions are further executable to:determine the first LBT priority class and the second LBT priority classare a same LBT priority class; and initialize the second LBT procedurebased at least in part on the LBT state.
 12. The non-transitorycomputer-readable medium of claim 10, wherein the instructions arefurther executable to: determine the first LBT priority class and thesecond LBT priority class are different LBT priority classes; adjust theLBT state based at least in part on a difference between the first LBTpriority class and the second LBT priority class; and initialize thesecond LBT procedure based at least in part on the adjusted LBT state.